Ok I have a new used engine purchased from qualityautoparts.com. I don't have the old engine from my 1974 chevy nova. It got scrapped before I could remove the flex plate or anything else for that matter. So my new engine arrived and the flexplate has a bolt pattern of 10 and 7/16" and 11.5". The converter on my car has a bolt pattern of 10". I have heard that they make a flex plate with bolt patterns of 9 3/8" and 10" but I can't fine one yet. Can anyone suggest anything.... There are some photos on my photo album.