Well, I'm making little to no progress with the top two compression rings on both pistons. I got the oil rings out with a little flux and some light heating from the inside with a propane torch.
For the compression rings i've tried breaking off even a piece of the ring with a punch and chisel, acid flux, soaking in atf paint thinner mix for days, boiling in water and also boiling in ATF, all of which has yielded only a slightly burnt finger and possibly destroyed pistons. I'm going to try a jig to hold a dremel with cut off wheel and the piston to see if I can get a piece out and see if the pistons are even salvageable at this point. If not, some new ones are $50-ish on ebay that look to have the rings all loose so I may have to just go that route.