The 1/2 ton front axle will be a bolt in swap. 1/2 and 3/4 tons use the same front springs.
3/4 tons used 9/16" u-bolts vs 1/2" on the 1/2 ton.
Don't forget to put the caster shims back in when you do the swap.


Steve

'49 3800
'52 3600
'57 3100