[Brabbit68]

The springs were chosen to match the cam and lifter combo, I do remember having issues with getting lash set correctly which is most likely what caused this. If I can't find a good keeper I'll bite the bullet and go with some new lifters and try to magnet fish the keeper out (assuming it hasn't fallen out already).

I think overall that's my best option at this point, because it doesn't make sense to rebuild the whole motor when no other issues are there and there are no signs of damage to anything else in the engine.

I think I dodged a bullet overall in this one (assuming the new lifter break in goes successfully).