I used modern axles, disc brakes front and rear, Scout power steering box, 241 transfer case, NP-541 trans on my first '47 GMC pickup, got factory full width fenders for front, works well, don't know if would have been easier to use modern frame, but that is another good option. I have a Dodge Cummins 4x4 pickup frame complete from gentle rollover, just looking for appropriate older body to put on it.

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.