cab fitting to frame

[fireguyfire]

I have my full rolling chassis fully restored, and am just finishing up welding in new rockers and floors on my 1970 d100.
I'm wanting to mount the cab back onto the frame for final fitting, as well as door fitting before I weld up everything permanently.
My gaskets to mount the body onto the frame were shot, so I will either have to buy or make some new one when the time comes.
For now I'm just thinking of bolting the cab to the frame with no rubber spacers for now for fitting; would this work? I'm not sure if the mounting rubbers are different thicknesses which would screw with my theory, or am I good to go at this trial fitting stage just mounting the cab directly on the frame cab mount spots?

[PwrWgnDrvr]

Front and rear rubbers are totally different, by an inch or more. Not a good idea.

[fireguyfire]

Can anyone give me the difference measurement between the front and rear rubbers? If I know that I could use a stack of washers as a temporary shim on the rear of that thickness to allow me to snug it down to the frame.
I’m doing a concept I’ve done on non unibody cars where you cut 4 18” pieces of 1 1/2” square tube steel and use them with threaded rod as a long spacer to effectively mount the body to the frame on stilts; allows you to work at a nice working height, you can weld from below if needed, and it guarantees your cab (or body) is perfectly fit to your frame so that when you remove the tube 18” stilts and drop the cab right onto the frame with new rubber it fits perfectly; essentially matching your cab to your frame; I’ve had great success with this in the past and would like to do the same with this truck cab.

[Wildergarten]

...effectively mount the body to the frame on stilts;

Interesting. Is the idea of this to preclude distortion while removing and welding in new body sheetmetal? I might not do the same thing, but the idea might impact the order in which I do my w200 body and might get me to pull the bushings and hard shim it first.

[fireguyfire]

That’s exactly the idea; got the idea from a high end 50’s car restorer; he said every time he drove a car that squeaked or tracked funny it was from a distorted cab to frame connection; if you do it this way you are custom fitting your cab to your frame