The TR6060 is a piss poor "upgrade" of the T-56, too many issues with 1-2 shift syncros, and 3-4 shift fork breakage...IMHO your better off looking for a Viper T-56 6 spd as it will have better internals, avoid the GM t-56 as it has a weak input shaft and is only good for about 450 HP max before breakage,..the Viper T-56 is good for up to 800HP, there's plenty of aftermarket suppliers offering everything from trannys to install kits for the T-56

Mike