I'm installing new rings in my 1.8 and I've been told two different processes so
I wanted to get your input as to which one is best

I was told that you can pull the cylinders and leave the pistons on the rod and replace the ring and then install the cylinder back on the piston while it is still connected to the rod.

I was also told that you can remove the piston from the rod and replace the rings
and put the piston back in the cylinder while not connected to the rod and then connect back to the rod.

What do you think

Whenever I build a motor, I have always set-up the pistons/rings first, then installed them into the prepped cylinders. Then I install them as a complete unit onto the ends of the rods and finally the case. I find it a LOT easier than trying to mess with doing the rings on a flopping rod and maneuvering a ring compressor around the 4 studs to remove it. . . Why hassle with that if you don't have to????

It's easier to replace the rings without taking the pistons off the rods. You save yourself the trouble of taking the circlips off.

BUT, you need a ring compressor that you can take off around the piston.

How do you clean all the crap out of the ring lands with the pistons still installed?????

That's just another reason I remove them from the rods. . . Everything is made more difficult IMHO with the pistons hanging on the rods surrounded by the head studs.

Exactly.
I've seen guys split the cylinder and/or break rings forcing a piston in without cleaning the lands.

Are you going to get the ridge at the top of the cyl removed so you don't break the top ring when you start it? The cyl's also require honing and that requires the cyl to be clamped in a fixture duplicating the block/head so the cyl will stay round.

No lip at the top of the cylinders, and honing is part of the process

Not much experience with T4s, but back in my dirt-bike racing days, i used to replace pistons and/or rings on a weekly basis (or so it seems).

Much easier to just pop the two circlips and take the piston off, give it a good cleaning, put on new rings, slide it back into the cylinder and then connect it back to the rod.