K10 to C20 frame

ptrckdillard

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Hello all,
New to the group and Squares, any help is appreciated. I live in the wonderfully over regulated state of CA. I have a 79 short bed K10 as a donor and I have a 73 C20 long bed. My question is, can the front and rear axles from the K10 be put on the c20 without modifications, I know the K member will obviously be removed but was curious if the mounting locations are the same on both frame rails?
Thanks again
 

AuroraGirl

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not a direct answer but here is a 78 k10 if you wanted some visualization
 

75gmck25

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Rear spring mounts are either 52” spacing, or on a few HD trucks they use 56” spacing. Other than that, the rear springs and axle should directly bolt on. I don’t think there is any difference in the front portion of the frame, but I’m not sure all the mounting holes for the 4WD springs are predrilled.

In that timeframe I think the cab has a removable center section in the floor, and 4WD or 4 speed cabs have a higher “hump” in the floor. I know my ‘75 K25 cab has the removable center floor hump.
 

yepyep

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I know its been done before but i dont think its easy google search k10 frame specs (use image search) ive seen diagrams online somewhere with measurements they are chevys factory diagrams do the same for the c10 and compare.

i did this recently for the rear frame (i had to add a section) but ironically its the only part of the diagrams i cant read are the rear sections so i cant figure out where to drill bumper holes or how long the frame is saposed to be

found these right off but the resolution sucks cant read the dimensions on my phone dunno if this will help you or not
 

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AuroraGirl

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400(?), 350
Rear spring mounts are either 52” spacing, or on a few HD trucks they use 56” spacing. Other than that, the rear springs and axle should directly bolt on. I don’t think there is any difference in the front portion of the frame, but I’m not sure all the mounting holes for the 4WD springs are predrilled.

In that timeframe I think the cab has a removable center section in the floor, and 4WD or 4 speed cabs have a higher “hump” in the floor. I know my ‘75 K25 cab has the removable center floor hump.
I think bucket has told me before the 4wd swap isnt so bad because most of that is there but going to 2wd would require some work because either rivets or holes for the 2wd crossmmeber stuff would require some measuring and mocking up possibly.
 

ptrckdillard

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Thank you all for the input, it's much appreciated. I'll be pulling the body off the c20 soon, so I should be able to find my answer on the mounting points/holes etc for the front. Thanks again
 

eskimomann209

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^no punctuation on the moon??

why anyone would ever care is beyond me

I mean, it’s horrible to read. Few areas I had to read twice to decipher the actual meaning.
Punctuation is really important when writing. You know the whole,

I helped my uncle jack off a horse.
Vs
I helped my uncle, Jack, off a horse.
 

eskimomann209

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OR..

I mean its horrible to read Few areas I had to read twice to decipher the actual meaning Punctuation is really important when writing You know the whole I helped my uncle jack off a horse Vs I helped my uncle jack off a horse
 

eskimomann209

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Thank you all for the input, it's much appreciated. I'll be pulling the body off the c20 soon, so I should be able to find my answer on the mounting points/holes etc for the front. Thanks again
CA technically titles the frame so good call there.
BUT if it ‘twas a me. I’d drill the rivets out of the door jamb and swap the vin plate onto the new cab.
I’d pull the dash pad off the 73 ( no vin notch) and slide it onto the 79 dash to cover up the other vin.
MIGHT even be tempted to pull the windshield and drill out the metal dash rivets and swap the whole cage over. This will eliminate the possibility of someone accidentally finding that old plate.
 

AuroraGirl

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I mean, it’s horrible to read. Few areas I had to read twice to decipher the actual meaning.
Punctuation is really important when writing. You know the whole,

I helped my uncle jack off a horse.
Vs
I helped my uncle, Jack, off a horse.
hey man I get it
10$ and a twix bar can go a far way and who are we, as individuals, to say no. warm holes are warm holes. (that was disturbing mental imagery even for me to say lol)
 

AuroraGirl

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Engine Size
400(?), 350
CA technically titles the frame so good call there.
BUT if it ‘twas a me. I’d drill the rivets out of the door jamb and swap the vin plate onto the new cab.
I’d pull the dash pad off the 73 ( no vin notch) and slide it onto the 79 dash to cover up the other vin.
MIGHT even be tempted to pull the windshield and drill out the metal dash rivets and swap the whole cage over. This will eliminate the possibility of someone accidentally finding that old plate.
wouldnt it be a legaler and also safer in his situation to get the vehicle titled with a new vin so it would be a 2022 or 2021(whenever) with a new VIN attached model year from the california gestapo.
 

eskimomann209

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wouldnt it be a legaler and also safer in his situation to get the vehicle titled with a new vin so it would be a 2022 or 2021(whenever) with a new VIN attached model year from the california gestapo.
The way CA wants it is, proof of ownership of both vehicles.
Then they want you to swap the 78 cab onto the 73 frame.
They’ll then attach the 78 vin to the 73 title and scrap the 78.
This can be done legally with bill of sales, titles and a statement of facts.
There is one other form that needs to be filled out I believe it’s form 256.
It’s pretty simple to do.
I just hate the fact that they push the destruction of the “parts” vehicle.
 

AuroraGirl

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The way CA wants it is, proof of ownership of both vehicles.
Then they want you to swap the 78 cab onto the 73 frame.
They’ll then attach the 78 vin to the 73 title and scrap the 78.
This can be done legally with bill of sales, titles and a statement of facts.
There is one other form that needs to be filled out I believe it’s form 256.
It’s pretty simple to do.
I just hate the fact that they push the destruction of the “parts” vehicle.
What else is a tyrant to do but make you suffer needlessly and ruin history for their enjoyment
 

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