Depends on whether you want to restore the truck or make a better runner out of it. The old 235 six isn't bad, but it's never gonna be a real stormer.
If it were me, I'd sell the six to a stovebolter lookin' for a motor for an older truck, then drop a V8 in. You'll need a bellhousing, as noted, because the V8s have different bolt patterns than the old sixes. Easy to find.
Check out how the motor mounts - they keep changing and offhand I have no idea how 62s were done. But V8s were stock in 62, so you can find mounts.
I once had a '64 1-ton worktruck with a stormin' good 350 in it, truck 4-speed, and 4.11 or so rear end. Ran great on the highway, at about 4 grand or so, but it could pass darn near anything.
Cheers!
George
