should pretty much bolt right in. you will be able to keep your clutch set up and the cable should work with the 3650 as well. you will obviously need a new shifter, and i dont know about the crossmember. driveshaft should work also.
personally though, i'd rebuild the t45 over the swapping the 3650 anyday. 3650 is junk, just got done taking one out of my car.