Chasing ghost

My 493 RB developed a strange noise. Started as a faint grown and getting louder. Last week I reached my stress level and decided it was time for exploratory surgery.
The engine is a 440 RB block, Indy EZ-1's, Eagle rods, Diamond pistons(10.8 cr), Eagle (4.15) crank, Comp (hyd flat tappet), Harland Sharp rockers(not full rollers), and Manly push rods.
I noticed a black stripe pattern on the inside of each valve cover. One in line with #2 intake valve, the other was in line with #5 exhaust valve. Uhh oh. Oiling problem!
Oil pressure never drops below 65psi. Checked all rockers and both rocker shafts for any trash/blockages. Clean as a whistle. With rockers and shafts removed I spun engine over and made a hellava mess on both fenders. No oiling problems!
Conclusion. Both #2 and #5 push rod cups were 0.073" deeper than the others. Both adjusters were black, but no gaulding. The cups were so deep that the threads just above the ball on the adjusters was rubbing the outside edge of the push rod cups.
I ordered a new set (Manton) push rods and adjusters/nuts from Harland Sharp. The way shipping is these days I'm sure it'll be a month or two before I get them.
Could the problem be two metal hardness differences?
Has anyone else had problems with Manly push rods or Harland Sharp bushed rockers?

sounds like you had the good fortune to get 2 bad pushrods. Quality control? I'm sure you'll be checking each one from the new set you ordered. Good luck! ruffcut

I built the engine several years ago and don't remember any issues with the valve train. I normally count the number of threads above the adjuster nuts for any inconsistent differences in height.
I'm hoping, like ruffcut said, misfortune getting two bad push rods. Strange it took almost 1000 miles to raise it's ugly head if that is the case. Seems like it would have shown up before now.
The black stripes indicate to me a deposit of fine metal. Which normally goes hand in hand with an starvation of oil. Resulting in signs of gaulding or traces of extreme heat. Which neither was evident.
I'm glad I found this when I did. But I'm not sure this is the root cause of the noise I'm hearing.

At any rate, I wish you luck finding the problem and not trash other parts!