All, I am an amateur, but like to do my own stuff. I believe my bathtub on second floor is leaking, as I see a rusty colored spot show up downstairs in the kitchen ceiling underneath the bathtub area. The plastic drain shoe and associated gasket underneath the bathtub is not almost completely stuck to the bottom of the bathtub drain opening BUT it's also off-center! I need to replace the gasket AND somehow center the shoe. I got some of the old gasket peeled off (trying to pry off the shoe), but cannot get a portion of it unstuck (from the back end of the bathtub hole -see pic). It won't budge. I've peeled off about 200 degrees of it (shoe is now a little loose).. As seen from pics, part of the shoe opening is (off center) flush with the bathtub opening (along the back end of the hole) and I cannot get a screw driver under there. As mentioned above, I think the biggest problem is that the shoe is NOT aligned with the bathtub opening and even if I was able to put the gasket in there (which I cannot since there isn't enough space), the drain flange will be off-center and not seat properly into the bathtub indentation. Can these things move forward/backward?? If not, I may be wasting my time. I'm afraid of breaking the piping underneath the tub and/or tub opening. EVEN if I can get it unstuck, I'm not even sure if the drain shoe will move forward to properly align with the bathtub drain cutout... It is sooo frustrating! (As an aside, I thought about just applying a wad of silicone around the remaining gasket/shoe, but that's just a temporary solution, as the drain flange won't seat properly (has been like this for years). Also, the overflow pipe is loose, but unfortunately that doesn't translate to the drain). Appreciate any thoughts!!!