most shift kits that ive delt with include directions on how to make your valve body more efficeint and raise the pressure in it. it comes with new springs and maybe even a new plate. you have to drop the pan of the tranny to do it. if you dont have much experience with cars, then i wouldnt do it yourself. ive put a shift kit in a 727 auto one time and it was a pain in the ***! i'd much rather replace a cam than do a valvebody.

 

http://www.baumannengineering.com/tcs.htm