833 manual to 904 automatic questions

So I’m in the process of swapping the original slant 6 and 833 out of my 1975 Plymouth Scamp and am swapping in a 1977 Slant 6 Super 6 with a 904 from a dodge aspen and am planning to put in a floor shifter with it. Is there anything specific that I need to change on my car doing this?
Sorry if this has been asked before.