Truck ID help

[bhayes1]

I posted the truck when I first purchased it, but wanted to follow up now that I have a little more knowledge of these trucks after hanging out on the forum for a while.

I've got what appears to be a 3/4ton GMC 2500 4x4 with a V-8, th350, NP205, AC cab, Power steering, Power brakes, LWB.

The truck has a cab with a vin the reads: CE149Z885524 and I pulled the frame partial vin that reads: 42Z109099

A few questions that I have:

With a cab vin that says 1/2 ton 2wd truck is it most likely that someone just simply took the sheet metal off a 2wd truck and found a 1972 4x4 frame and did a swap?

The bed has a fuel door but no fuel tank. Tank is still in the cab behind the bench seat. Any ideas what the bed belongs to. It also has the cargo door on the passenger side.

The SPID is not readable.

The title says chevrolet. Do both GMC and Chevy trucks say Chevrolet or did someone take the time to swap out all the chevy badges for GMC?

Anything else you guys see feel free to chime in.