YC 176A is for an International 6 cyl FAC241, 259, RED401, 450 YC 316A is for 52-54 ford V8 279, 317cu
This is the Mallory YC 316A...with a 6cyl cap. Looks like its machined a bit on the shaft. What do you think?
Someone was probably mixing-n-matchin' some parts back in the day, they could have whittled down the end of the housing down in a lathe and put a 6 cyl cam in it to build a custom distributor for something.