On my ‘55.2, GMC I put disc brake hubs/spindles from ‘91-‘01 +/- GMC P-3500 HD with tie rod behind axle on my stock front axle. Needs to be 2 ton or slightly larger axle with steel six bolt hub cap. Tires stay inside front fenders.
King pin diameter can be shimmed or new bushings($12. each) made to make up diameter. Axle thickness at king pin must be same. Easy to do.
Delphi(Saginaw) power steering also installed.
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.