[Ford blue blood]

Are you pulling the heads during this rocker shaft rebuild? With stock springs, a relatively hot cam you should get years of service from the stock set up.

The problem with oiling the top end is rooted in the oil routing to the head and the fact that older oils used "back in the day" did a really crappy job of keeping the oil clean. The passage for oiling the top end make two 90s on it's way up' The oil hole in the block is off set from the hole in the head. There is a small groove in the head that hooks the two together. That is the culprit. Pull the heads and clean both holes up and down, clean the groove or enlarge the groove slightly and live happily ever after. New oils keep the transfer groove clean a gagillion times better!