2000GTBoy

So i have a automatic and i hate having a muscle car and its an auto. So i plan on installing either a tremec 3650 or T-45 idk yet. I was just wounding what do i have to do besides switch tranny, add clutch, clutch assembly, hydro,shifter.
so if i could get some opinions on wheather to do it or not. and if so which tranny, and what other **** i have to do?