If you're going to replace the front suspension, make sure you pull it out as a whole unit, cause the torsion bars are under alot of tension.
I'd use a '63-'84 gm front clip, and 4 new holes will be needed to be drilled. You'll have to use the tie rod linkage & idler arm set up off of the same donor truck. Also when swapping out the torsion crosmember, you'll loose the front engine mount for the 235 since it's riveted to the saddle. If you plan on keepiong the 235 in the '62 for awhile, i'd weld it to the front of the new saddle.
I plan on doing this swap eventually too, after I swap the 235 I6/3 speed for a 350/350 setup.
Or if you're wanting to make your truck a swb, find a donor swb '63-72 GM truck frame, or even better, a '71-72 swb chassis, and it wil have 5 lugs with disc brakes.
David