" From: Jesse <j2sax@xxxxxxxxx> " " I guess I didn't ad enough clarification to the " original question, though some of the responses were " salient. I assumed that everyone would know that the " adapter I was talking about was from an AMC 304 to a " TH400. The Buick engines were mostly done by 71. yup. the confusion is because the buick adapter has a standard bop pattern on one side, and many folks confuse which side that is. a different adapter was used with nash 327s and th400s before that. " So, to review, the AMC V8 to GM TH400 adapter was only " used with an odd GM TH400 that did not have the " standard GM bellhousing pattern. Instead it had an " "export" pattern? Bummer. yup again, though that case was first made for the nailhead buick - 401 by '65 - and the necessities of that block made the case a good export platform. you might be best served by the advance adapter ring, which bolts to the amc block and has both chevy and bop patterns on it. ________________________________________________________________________ Andrew Hay the genius nature internet rambler is to see what all have seen adh@xxxxxxxxxxxxxxxxx and think what none thought