Congrats on finding your car's original owner and history. It appears Mel Perry gave your Chevelle some of his modifications before the car went out the door. Keep digging. Hopefully the original owner still has some documentation (build sheet, POP, photos, etc.) to support what options the car was originally assembled with, and the modifications he says were made by Norwood Motors.
Here's the thread on my 1969 L89 Chevelle that received Mel Perry's modifications at Norwood Motors, according to the original owner.
https://www.yenko.net/forum/showthread.php?t=141828
I like how you modified your asking price to NFS!! She's a keeper.