The ones with the splines machined under the t/o bearing coller were the Muncie 3 spd.transmissions with the 4 bolt side cover.GM quit using them in the mid 1960s.Both will fit V8 or 6 cylinder engines,but the 6 cylinder one was not a good idea behind a V8 with a heavy foot.The Saginaw 3 and 4 speed transmissions are from the same transmission families.The transmission shop that said the OD unit could be installed behind the Saginaw 4 speed was Transmission Exchange in Portland,Oregon.There is lots of Inliners club members in the Portland area that might be more helpful.There was the Tip Toe Matic overdrive unit made in Portland,but I think it was only made for closed driveline cars only.I once heard of a unit called a Watson box,but no nothing more about them.
EvilDr235
------------------
Two types of people drive old cars.Rich people because they want to and poor people because they have to.
Remember EvilDr235 has a cure for Your sixness.
