I removed a poor tile and pan job from my bathroom that had been leaking thru the rubber liner into the studs and exterior OSB. I've replaced the wall studs and OSB that was rotten and I'm thinking of going with a shower pan and walls from DIY showers. Here is a picture of what I have as a drain right now. Can't I just cut this off with an inside cutter, add a coupling to extend the 2" pipe up so it meets up with the pan then use the caulkless drain? Or, does that PVC glue dissolver stuff work? Could I use that? I'm trying to avoid cutting into the existing concrete.... Appreciate any advice.