piston rings
cast iron rings needed to be lubricated by the familiar cross hatch pattern a hone (dingle ball or stone) to seat properly. Chrome rings needed a smoother bore and finally moly rings needed the smoothest (ie. seasoned motor polished) and they required almost no break in time, maybe 200 miles. If you get new rings and dont want to scuff the walls with a hone, get chrome or moly rings. I reringed my smoking tired 2.0 mazda truck without honing, installed moly rings, checked valve seals (they were good) and started it right up. No more smoke, more power and I have put 16000 miles on it without a sign of smoke. Iron rings needed the roughest surface to seat, chrome was smoother and moly is almost polished. Id do valve seals first, then wouldnt hesitate to rering the motor with it still in the car, especially a slant. Easiest motor to do with exception of the oil pan rail almost sitting on the frame. Stuff some poly rope in the spark plug hole, bring piston up to TDC and use valve spring compressor to pop retainers off without losing the valve, R&R the seals and give it a drive. Much easier than a rering. About every LA head I dealt with had rock hard seals and 50% were always missing, Id find the pieces in the pan.