Re: Accessing waste pipe
The good news is that (see pix) I have accessed the Waste pipe from below. Note what appears to be corrugated pipe (ugh!). The question is: how is this project going to work?
I can't just rip the whole thing apart and replace the pipe and deck fill together because the holding tank is full and the waste cap is galvanically corroded in place (tried boiling water, vinegar, liquid wrench, etc). So, I have to replace the deck fill assembly using the current pipe, refasten temporarily, then pump out the 'stuff' and cleanse the tank, and then replace the pipe starting back at the holding tank. I have some advice on the correct smooth white pipe to use for a replacement.
Besides the hose clamp, there is some tape, which seems to have been painted over (?!) and a plastic nut above the hose clamp and a 2" sleeve of some kind which goes around the incoming deck pipe stem of ~1.5".
Welcome suggestions for a clean method of proceding.