I had the rocker assembly rebuilt at a shop in California and didn't think to look at the numbers cast into the individual rockers after I got them back. It's probably too late for that though!

As far as getting the block oil passages blocked, not only will filtration make a difference, so will detergent oil, which I don't believe they had in 1962.

'51 Chevy 1/2 ton w/'62 261, HEI, offy, fentons, dual carter/webbers, t-5 & 12 bolt posi