It actually is...just not a commonly used one as its late model and hydraulic clutch. Here's the info:
4471829 1 D 10-3/8", 11" Clutch, A535, A435, A833 Transmission, Except Diesel Engine 1990-91
Also...my BB 833 bell bolt holes match this one but with a smaller Center hole.
I also had to look at the first pic several times to figure out the angle and what I was seeing. I would also pull the bearing retainer to see if it fits the early bell. My only guess might be that the case was slightly re-engineered with that hole slightly off.
