Flattening the Floor to Allow Use of Any Seat

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xm20k

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Ya, pricey is right, TMI configurator had me at $5700+ for tan colored bench seat with console and bracket, mama mia!
I figured it would be ridiculous based on the non-custom stuff so never even bothered to go to their site and look.
 

Sad Sack

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I figured it would be ridiculous based on the non-custom stuff so never even bothered to go to their site and look.
If my truck was worth $40,000 then maybe...
 

xm20k

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If my truck was worth $40,000 then maybe...
I've put more than that in mine since buying it 2 years ago and still not worth it. :oops:
 

Camar068

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Pretty sure there's a post/sticky on removing the saddle tanks and then getting rid of the humps to allow ease of installing whatever seats you want. Been a while, but I'm pretty sure it's here on GMSB.
 

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The stock tanks sit up in that hump quite a bit, I pulled mine and put a cell in the bed, because my exhaust needed to run under there. The senders are right were the bed and cab meet you can see them thru the gap.
Since gas doesn't store uphill well, I guess I'm going to have to pull the tank to check it out.
Trying to go for this look?
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Too many people mention the electric seats lift you enough some had to swap steering columns, others complained of being awfully close to bouncing their head off the ceiling in a rough ride.

Even getting the seats down 7" would be great.

I know I had to cut the pedestals of the captain's seats I installed on my 69 down by several inches to get a good fit. After that, that would be the way I'd go, were it not for that anything remotely like what I had goes for at least fifteen hundred.

Here are photos showing why playing with the mount brackets is not a solution.
 

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Dejure

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Pretty sure there's a post/sticky on removing the saddle tanks and then getting rid of the humps to allow ease of installing whatever seats you want. Been a while, but I'm pretty sure it's here on GMSB.
Looked for it, but couldn't find it. Apparently for want of the right search words.
 

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Even before I start, I suspect I'm going to have to drop the tank just to get the passenger seat bolted down. May go that route to see how it goes, but need to get the power set up for the seats (fuses and relay) before I start.

After that, it's a matter of figuring out what to do with the old bench, which someone had redone (couple minor blemishes).
 

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Dejure

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Or ditch whatever brackets come on your preferred seats, use universal style sliders (or none at all) an do this.

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Electric seats, so. . . .
 

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Electric seats, so. . . .

The brackets an all that still unbolt or can be removed from the actual seat frame. You don't have to use it just because its on there.
 

Camar068

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Dejure

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The brackets an all that still unbolt or can be removed from the actual seat frame. You don't have to use it just because its on there.
There would be little to nothing gained by doing away with the factory brackets, unless I abandoned the electric components.

Then, I'd have to shop around for standard slides. Not only would that negate the purpose of the electrics, I suspect it would be a pain to locate the right brackets, and to pay for them.
 

Dejure

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The GMT800 information is gold for what I want to do because, like with his, I will be able to put ANY seat I want in. Including the ones I have and that would push me up against the steering wheel.

(https://www.gmsquarebody.com/threads/gmt800-nbs-seats-in-a-square-body.375/page-7)


The ONE MAJOR DIFFERENCE is, his is a fleetside and is fueled from high up, while mine is a stepside with the filler in the rear fender. You actually have to bend over to fill it (way to go, Detroit - see avatar image).

That means, if the tank actually pops up under the passenger seat hump, that extra few gallons is wasted tank, because the fill port is lower than the bump up.

Some indications have been that some of these tanks have fill ports in different locations to deal with the difference in where they are filled from, depending on if you have a stepside or a fleet side.

Below are photos showing the tank viewed from that rear fender well showing the fender fill port, AND on of several, similar examples of replacement tanks for the step side version (C15). The latter that suggest the hump is not filled by the top of the tank. Instead, the part under the seat is lower than the fill port side. Again, my avatar photo shows the location of the gas cap low on the rear fender.

SIDE NOTE: IF the sender is the same on both fleet sides and step sides, but there is a bump up under the seat, that would explain why so many of us note gas gauges, sometimes, seem to stay on full a long time, then drop quickly.

That is, the gauge really doesn't accurately register the gas in the tank until it gets down to the lower top level.

Any way, this would suggest I may get lucky and be able to use the tank even with the seat base lowered.

Alternately, I MIGHT be able to lower the tank one or two inches and not have to move it. Leaving ample room to hide a spare at the ass end.

Only dropping the tank will give me the full story.

Mean time, may have to develop an attack plan. Things like temporarily moving the tank into the bed, with an extra long fuel line and a bit extra gauge wire, to allow use of the truck, if only to get to where I need to be to weld it.


It's @Old77 post an its a sticky at the top of this forum. GMT800 NBS Seats in a square body
 

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Dejure

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To be clear, my 78 C15 stepside does not have saddle tanks. It has only the one tank, with the filler visible in the photo, at left.
 

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