Re: Leg swap
If the years of your early Chrysler and late Chrysler are correct, while the legs may look identical they are different. Unless you are going to use the lower unit they came with, they will not swap. Engine mounting bolt pattern, match plate, power trim/tilt and transom clamps are the same but the lower unit bolt pattern is different.
If you intend to use the complete leg with lower unit, then yes, they will swap. I did this a while ago to prove to myself that the 1980s lower unit was indeed faster than the 1970s lower unit as advertised by Chrysler back when they developed the one piece lower. Yes, the one piece lower unit is about 3 MPH faster than the two piece lower unit of the early '70s.
