Have you seen the Oct. '69 Laks Chevy ad on this page below?.
Maybe your Biscayne was one of the remaining 69's w/ huge discounts!.
http://fultonhistory.com/Newspaper%2011/...%20-%200600.pdf
Longshot worth confirming and sorry if I asked you this already but what's the build plant of your L72 car Zach?.
Considering the proximity to the Oshawa Canada B-Body plant, it'd be all magical if the car was Canadian built thus GM Canada Vintage paperwork available!.
[img]<<GRAEMLIN_URL>>/beers.gif[/img]
~ Pete