Hi John,
I have a 68,(seems I'm always forgeting something even after proof reading several times). Is bakelite the heavy brown/black cover with the flecks of light brown, it also has a rough texture. I believe this came off my old 67 Camaro, it was mostly original. The one I removed from a 68 Nova is very similar,but is smooth textured and a little darker, could be black,both have Delco-Remy and Made in the U.S.A. in the same location below the positive terminal. Any idea's for 68? thanks