Okay, so I'm in the middle of a head gasket replacement. I have a 2000 monte LS with the 3.4L all stock, 135,xxx miles. I have got everything pulled apart and there was coolant in cylinders (hence why im doing the job). When i soaked it all up, it seems like the pistons are loose. Like I can move them side to side a little more than the thickness of a piece of paper. Not much but they move. Are they supposed to super snug or have a bit of play for when they heat up and expand?

Also how do i check for rocker wear and wear on the lifters (rods with rounded ends that push on the lifters? Do i need to?

Thanks all!!!