69 rear leaf spring u-bolts

[69bigblock4speed]

Thank you for all of your resonses and time. It is final. Black I believe was the color. Now I will decide to go with Black Zinc oxide or the Manganese route. Thanks again.

[68camaroz28]

Thank you for all of your resonses and time. It is final. Black I believe was the color. Now I will decide to go with Black Zinc oxide or the Manganese route. Thanks again.

Everyone I know including myself use the Manganese Phosphate for the black hardware. Not stating its the best, but know many using the Manganese and have good results. Also, you asked about dimensions and that one link I posted from my build thread gives the dimensions.

[Edgemontvillage]

Thank you for all of your resonses and time. It is final. Black I believe was the color. Now I will decide to go with Black Zinc oxide or the Manganese route. Thanks again.

According to the late John Hinkley (John Z) a former GM engineer at the Norwood OH plant during 1969 production who posted on the subject here, GM didn't spec zinc oxide as a finish as it was not cost effective (one exception he noted was for the 5 panhead screws that attach the instrument panel on the 1967 Corvette). Instead GM spec'd manganese phosphate or zinc phosphate. We use both in our shop and when compared side by side, they are different. Zinc oxide is a true black finish and cures/dries to a semi-gloss whereas manganese phosphate, also referred to as black phosphate (used interchangeably in the Legends Judging Manual) dries to a near flat finish (unless well oiled) and depending on the ferrous content of the metal can appear mid gray to black however typically cures/dries to a dark charcoal. If originality is a goal then phosphating is the correct choice.