strut rod adjustment cam bolt assembly

[Don H.]

Good morning. I could not find this discussed in any threads in the archives. The strut rod adjustment cam bolt assembly lacks the notches that all the others I have heard of have. My car is a Jan 64 coupe.
Are the bolt units shown here someone's poor reproduction, or factory anomaly, or something else?
The headmark is M and there is a large M stamped into the backside of disk.

[Joe L.]

Re: strut rod adjustment cam bolt assembly

Don-------

They are legit and likely originals. Early C2 cam/bolt assemblies did not have the "degree" marks. They were added later but I just do not recall when. However, the part number for the assembly, GM #3820253, did not change when the marks were added. It remained the same until the 1977 model year when it was replaced for PRODUCTION and 1963-76 SERVICE by GM #458979. The most notable, if not only, change that occurred was that the 458979 was completely zinc plated. The 3820253 had a black phosphate finished bolt and, usually, a natural steel attached cam. The separate cam, GM #3790331, was always zinc plated.