Craig,
New here on the Stovebolt as of this AM. Absolutely blown away at the progress of your build. I am excited to do basically the same project as yourself, and would appreciate your input (as well as any others )
My 59 was a 6cyl. Standard. I am also going with a 327 but mine will have a turbo 400 automatic trans.(Pontiac GTO).I have cut out the stock center crossmember in exchange for new ones. I have purchased both motor mount and trans mount crossmembers from CPP. My questions are, can you advise me as to the correct location on the frame for these crossmembers,based on your build? Trying to avoid the mock up process (if that is even possible.
Being a beginner both here on the Stovebolt as well as with custom builds,
It is quite the eye opener to see folks like yourself who can fabricate your own mounts and position accurately. I will try in the next few days to add some pics of my project. (Still learning how).

Thank you and anyone else for any guidance