LSWNDR

I just aquired a TH400 recently and i am debating wether or not i want to put it in the car. I am having stock master cylinder problems right now an i am thinking about getting rid of the 6-speed totally, but the only thing is i drive this car daily an i still do roll racing so i am trying to decide what i'm going to do about this debate? I love the six speed because i have no issues with perfect shifting, but i know this 408 is gonna murder the T-56 when the bottle gets installed.... Any information about this TH400 that it takes to get it into a f-body that i should know would help me out alot guys thank you.