First swap, what should I expect?

I don't think you can use the bell housing, "too big" for an A. Same with flywheel which is larger dia than passenger car ones. You need to change the pan from rear to front sump. I don't think the exhaust manifolds will work, although pass one might.

So far as the 3 speed determine "what it is" (post photos, numbers) and I'm sure you can do a floor shift.

You will need different engine brackets, not the truck ones

WHAT IS in your car now? If it's a 6 you'll need a different K member or modify that one, or use "swap" mounts, which lately are kinda ?not? ?maybe? available.