From what i've learned so far they are a seemingly crucial part of the engine working well.

Not really, it's just that when heavily grooved, it makes it harder to set the tappets & the are always going to be extra noisy, but solid lifter cams are noisy anyhow. With stock to medium sized cams, there would be no difference in power between old rockers & new.

I used whatever rings the initial builder used

Are the oil rings at least the modern three piece Sealed Power type & not the ancient old one piece iron things?

Was the top ring chrome plated, plain or moly faced? Chrome really sucks to bed in.

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Three 164's, Two 144's, One 142 & a partridge in a pear tree.