My engine builder wants to build a plate for his dyno so he doesn't have to use the bellhousing to hold my 401 in place for dyno testing. I tried the search function, but it didn't come up with what I am looking for. Does anyone have a PDF or a CAD drawing or print of the bolt pattern at the back of the engine block and the the 4-bolt pattern on the bellhousing-to-tranny connection? If these bolt patterns were shown superimposed that would be even better.

I can read any common CAD format so if that is the flavor you have it in, that works as well.