72 chevy
2F374901 = 05/2x/72-05/31/72 (post 283)... Pretty certain I see an "E" for the build month.
71 Blazer
1F654299 = 06/15/71-06/25/71 (post 283, Blazer)
72 chevy
2A127953 = 12/71 (post 283)
68 chevy
8Z119022 = 11/09/67-11/29/67 (post 283)
72 chevy
2B129385 = 01/05/72 (post 283)