Where it sits on the frame is where you want it to be. Is your 54 a long box or a short box? The reason I ask is because the extended cab frame is the right length for a long box 54, but need to be shortened for a short box.

The reason there is no "measurement" is because it depends on exactly the look you want. We have done several of these swaps now, and always place the cab on the frame with the front end assembled to the cab so you know exactly where to set everything to get your wheels where you want them in the wheelwells.


1946 GMC Pickup - S-10 Frame, 455 Buick, TH400, original patina.

My 46 GMC on Photobucket