Factory GM Guages ADD tach?

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Has anybody here done the Factory Tachometer ADD to the GM cluster offered through LMC?

You replace the huge fuel gauge with a factory looking tach and place the fuel gauge over in the small gauge clusters.( in my case replace the huge BRAKE light with a fuel gauge.

In order to do this change you need a tach, wiring for the tach and the Mylar wiring schematic for the back of the gauge cluster?

Thought comments?

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RetroC10Sport

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It can be done, but it's a pain.

I do plan on adding a factory tach and fuel gauge to my daughter's '73 Cheyenne when we get a chance. I have one that works, just need to get the wiring for it. I will be adding it to the cluster but just running the fuel gauge wires to a custom connector separate from the mail cluster.
 

Camatruder

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I did the conversion a couple of years ago on my '91. It's not exactly the same as a '73 but very simular. All wiring was included or ordered separately, can't remember. What i can remember is that it was not very hard to do. I did find some pics.
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Camatruder

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I did had to install an emc filter afterwards, the needle of the tach was too shaky. Found that on ebay.
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Best truck design

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Thanks I love the look of the factory gauges and think GM was at their peak for truck design back in the 70's. IMO this is the best looking truck that was made (dash included).

I will be doing the conversion at some point.
 

Best truck design

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I did the conversion a couple of years ago on my '91. It's not exactly the same as a '73 but very simular. All wiring was included or ordered separately, can't remember. What i can remember is that it was not very hard to do. I did find some pics.

Did you get your gauges from LMC?
 

Camatruder

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yes i did.
 

usar17

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I did the conversion a couple of years ago on my '91. It's not exactly the same as a '73 but very simular. All wiring was included or ordered separately, can't remember. What i can remember is that it was not very hard to do. I did find some pics.
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Exactly what I need to do! Couple questions.

Did you have to cut the hole for the tach connectors?

What kind of connections were on the fuel gauge?

Did you have to modify the bottom left hole any for the fuel gauge to fit since that's normal a blank with just battery indicator?

Did you do anything with the battery light?

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Honky Kong jr

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Exactly what I need to do! Couple questions.

Did you have to cut the hole for the tach connectors?

What kind of connections were on the fuel gauge?

Did you have to modify the bottom left hole any for the fuel gauge to fit since that's normal a blank with just battery indicator?

Did you do anything with the battery light?

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5k rpm meh not enough lol
 

Camatruder

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Exactly what I need to do! Couple questions.

Did you have to cut the hole for the tach connectors?
Yes, see pic 2 in post #3.

What kind of connections were on the fuel gauge?
I can't remember having problems with the fuel gage. I proably just connected the 2 wires from the old big gage to he new small gage.

Did you have to modify the bottom left hole any for the fuel gauge to fit since that's normal a blank with just battery indicator?
yes, a little, see same pic.

Did you do anything with the battery light?
Well here i went wrong at first. I first connected the light to the instrument cluster lighting to use it for my new litlle fuel gauge, but every time i put on my lights the alternator stopped charging the battery, you know battery light on, no charging. So i simply disconnected it. New litlle fuel gauge is in a kind of dark place at night but it's not that i have to look at it much. If the battery was not charging i would see that on my voltage gauge.

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