Welcome to the board.

Adding a 4bbl in place of a 2bbl was the first thing I always did when I acquired a new to me Mopar. Standard procedure!

You will need to change the intake manifold, the carb, the air cleaner assembly, and you will probably have to slightly modify your throttle and auto trans kick down linkage, the 4bbl stuff sits outside and slightly higher then the 2bbl stuff did. Sorry, I don't remember exactly what I had to do with the linkage, it was a long time ago.

If I could limit how often I put my foot into that 4bbl, most of the time, adding the 4bbl improved my gas mileage! Gene