guys im not sure what it is out of/////i was told a 66gs .. it was bolted to a 401 nailhead .....i was told it could be a sp300 but i counted the detents and get6 which indicates to me a 3 speed ?????so what can i do to find out for sure ????thanks pete
Pete, Best thing to do is borrow a digital camera, take a picture, and post it. If it is an ST-400 out of a 66 GS, there is a metal tag on the passenger side of the trans. The tag will have a 2 letter code. It should be BS, and the year 66 should be stamped into the tag on the bottom. That trans would be behind the 425. If the tag says BR, it is still a ST-400 but came behind the 401.