o6 gmc 3500 duramax getting a 50's peterbilt cab

[68 CRACKERBOX]

I don't know if this is the right place for this build. but this is what we have bought a 06 k-3500 gmc flatbed someone tried to put a lly in it I don't know what happen to the org. engine should have been a lbz. but they could figure out the wiring diffances between the two so I brought it with the lly & the short block of the org, engine laying on the bed.
I took the cab off I had a lmm from a 07 here already so I'm using that, with the 6 spd allison was still in the frame. so I'm at the point now building cab mounts and rad mounts.