Going back the oil thread, I just miked quite a number of the brass pucks and came up with essentially 2 different sizes. .45" & .48" with, at this point, no known reason for the difference. I'm tossing this out so you can check yours, number one to see if they match and number 2 to help you determin an oil weight to run. The smaller might favor 20wt and the larger one might favor something like ATF which we've run for years.

Just something to check when you all are totally out of things to do.

I just ran out and checked mine but I'm not certain that I'm measuring in the right place because I get right at 9mm which is 0.354". This is the widest part of the small cylinder at the bottom of the SU dipstick. As far as I know these are original SUs from a 9/71 car.