440 rear main seal... thoughts

Did you compare the crush distance of the block side to the seal cover side of the seal?
I forgot which aftermarket brand I was given to use, but there was a significant difference. About 0.030" from memory. Which means one side of the seal is crushed more than 0.030" than the other side, instead of being centered. I ended up using the factory seal cover which was more consistent. Pretty doesn't always mean good.....