Hi, I have a sewer cleanout in my garage. It is a 3" pipe but the plug size is 1.75", it a appears to use an adapter or reducer. I would like to know if it's possible to remove the reducer and upgrade the opening to a larger size plug, so I could use a mainline snake with a root cutter. The cleanout is surrounded in concrete and pretty much flush, see pix.Thanks very much for any help!!