Drive shaft swap

I put a 4 speed in my 68 Barracuda and a 8 3/4 rear ,got a drive shaft out of a 74 dart manual transmission and it seems like the input shaft goes in too far. Looks like it goes in an inch and a half further than the original wear mark. Should it work or are they longer on the later A bodies?
Just a thought.. the dart has a 111" wheelbase, your cuda will be a 108"