My original drain screws were a bit chewed up from previous owners, so I bought a new afermarket set..... then I drilled the old ones just big enough for a plastic straw to go through for a real snug fit (in other words, I didn't use any glue or epoxy, maybe you should).... then I slipped silicone clear tubing onto them and used them as my clear tube tools. I could not find 6x0.75 adapters either, so used what I had.