Tom, you let the rocker arms mill from a aluminum block currently, is there also a needle bearing on shaft or the same like original, maybe bronce liner?
Was being done with aluminum block. Aluminum on steel shafts as original. The originals wore the steel shafts & NOT the rockers. No sense adding rollers or bushings as there is not enough movement. The angle would only put pressure on one side of the top & bottom rollers & cause other problems. TomT.
A couple of years ago I bought some equipment from a business that went belly up called "Powdered Metal Products" here in the Chicago area. Apparently they had a contract for years with GM making transmission gears, among other parts, for GM from powdered metal. They lost the contract and closed their doors. I was surprised to learn there is a large percentage of hard parts created from powdered metal in an automobile's content. Tom Mooney