52 Caddy Eng/Trans swap info

[Tom Kieffer]

Just acquired a 52 Fleetwood wothout eng/trans and need confirmation that  the 365 eng/trans will bolt in. My rig is missing the stock 331 eng/trans and Im exploring all possibilities. 331 vs 365 is only a bore difference correct? Forget the 6v 12v differences.
 
How about the later 59-62 or 63 390 eng/trans?
 
Im more concerned with getting this caddy on the road than number correctness.
 
Thanx in advance
Tom Kieffer
Merlin, Oregon