I went through this with my 1989 103 engine. at 220K. There was absolutely no ridged to talk about. These blocks are probably carved from a solid granite block as there was absolutely no wear on the cylinder walls.
I also needed to replace the oil pan gasket (major leak).
First, unbolt the connecting rods. The order has no importance. Make sure you keep the connecting rod caps with the rod they were with. Do no mis-match the rod/bearings/caps. A gentle tap with a piece of wood from the bottom is all that is required to get the pistons out. Make sure you clean the ring grooves. You can get (rent) a the tool at any good auto-parts store. It is a kind of narrow scraper that fits in the ring groove. Do not remove any metal, only carbon and deposits.
Installing the rigs is easy. be carefully not to brake or bend the rings while installing on the piston. Go slowly. The ring compressor tool fits around the piston when the rings are installed. It makes it much easier to re-introduce the piston in the cylinder. Again, a little tapping with a piece of wood is helpful.
Rod bearings: Look at their condition. They should be ok with your relative low mileage. For more assurance, you may want to replace those too. (not expensive). Your oil pressure should go up a little.
Again, at the stage your at, this is the smartest thing to do.