I need to remove some plaster wall inside a closet to gain access to my bathroom waste pipe. I was wondering whats the best way to remove a section of plaster wall, can it be cut with sawsall or circular hand ginder? Never done this before and should I repair the wall with drywall or plaster? Thanks in advance.

. I have never had such difficulty in removing wallpaper as this. I have tried using plain hot water, and hot water mixed with dawn, hot water mixed with vinegar, and DIF./ After scoring the top vinyl like layer I am able to remove it gradually, but am left with the backing paper which, after soaking well comes off in tiny bits and in places removes the paint in a skin thereby leaving bare drywall showing that the glue is a stronger bond than that of the paint against the drywall. So far have got about 20% done which has resulted in a mix of surfaces some drywall , some glue, and some backing paper which wont all come off. Before I go onto the next section, I need advice as to whether I should try to leave the backing paper on intact after removing the vinyl and if so what is the best way to prepare and paint. Some of the bottom edges are lifting and some areas the paint skin is just hanging down. The wall itself is textured and painted with a semi gloss. Being as the damage is near the ceiling could I get away without texturing and just filling in the gouges and maybe trying to feather the edges of the paint skin.