I use a 3550 tremec in mine love it to death. I can't put 60K miles on it like Hal has
. Both John Bennett and B&B recommend the tremec. Mine is a 5 speed. Mainly use the 5th gear as a "gas milage gear" on long trips. I can't imagine using a 6 speed in these cars due to a moderate top end. What is equally important is the clutches,bearing,and bellhousing. Often not given as much thought as the tranny.