Roy & Georgia

Hello all! I am hit with a dilemma. The wonderful black tank. While cleaning it out using a flexible wand I found it had started leaking when I flushed it out with water. I was trying to fill it to the point of coming up in the commode (maybe not a good idea) and it started leaking out the side of the corroplast. Obviously I am going to have to remove the corroplast but I'm not sure where it needs to come down. Am I going to have to remove the whole thing? Just trying to get some insight and recommendations before I proceed.

15 375flf, 12 f350 swd