I'm going to pull the transmission in a week or so so I can check what Bellhousing is in there. I think the weight of the flywheel makes more difference than the size to me, and I'm after as heavy as I can find. I am assuming that all of the standard chevy bellhousings are the same depth from face of engine mounting surface to face of tranny mounting surface? I can't really afford any extra length as the SM465 plus adaptor is already two inches longer than the T90 with adaptor that's in it now.