Hi Blackjade,
Welcome to the fold.
I'd recommend that, if you don't already have one, get a copy of the most recent SAAC Registry for these cars. Many of the revisions are mentioned and that should serve a a great starting point. After that, spend a few days reading through the '69/'70 section of this forum to get acquainted with some of our members, then reach out to those members with specific questions. Several are judges and highly regarded authorities with decades of personal and collaborative research. They may have some bandwidth in their schedules to answer a specific question, but be patient. Many of us enthusiasts, who are DIYers may be able to answer some of your questions, based on personal observations.
As Coralsnake alludes, post pictures of what you question. It'll help with clarity and specificity.
Here is a thread that may have some information to help:
https://www.saacforum.com/index.php?topic=11172.msg95178#msg95178Good luck with your research.
Steve