Thank you for thinking of me and that yes I am still looking for a correct bumper jack for my 69 FB Oct68 build)
The black colored jack is most likely a Camaro and you can see subtle differences in them. As for the blue one it see,s to have the lighter color which is significant of 2nd Gen FB's but that doesn't mean that it is one. From all of the examples I have seen they all had the stamp on the rivet. Typically it is a two digit code giving the year with one number and then a letter indicating the month. The blue one has a 8 stamped into it which seems odd. What is the length (in inches) of each jack shaft?
ETA: The black one looks to be from a A-body style car as the shaft looks to be thicker. Typically when looking at the shaft there will be two lines creased down the center which that one has. F-body cars had a thinner and light shaft.
