Send us a px, give us a idea of what you want in the end, we'll give some ideas.

My input would be, if you don't want to keep it exactly original, but a driver, would be to put later axles, hydraulic brakes, steering under it. If not a flathead in it, what is it?

GMC engine SN's start with displacement, i.e. 228xxxx, etc. if an overhead valve. Stamped number on pad behind starter on starboard side, port side on big engines.

Ed

'37 GMC T-18 w/ DD 4-53T, RTO-610, 6231 aux., '95 GMC running gear, full disc brakes, power steering, 22.5 wheels and tires.
'47 GMC 1 ton w/ 302, NP-540, 4wd, full width Blazer front axle.
'54 GMC 630 w/ 503 gasser, 5 speed, ex fire truck, shortened WB 4', install 8' bed.
'55 GMC 370 w/270, 420 4 speed, grain, dump bed truck from ND. Works OK.