Hal, the main drain pots should either have a sleve to glue a pipe into or a threaded sleve to put a male adaptor into (if it takes M/A -male adaptor, threaded - don't teflon the threads, GLUE them in, a leak in one of those would mean either abandoning the drain or jackhammering up the bottom to fix it). The anit-vortex is just a different cover for the unit (they're round). Have a level on hand when attaching the drains to the pipe so that you can be sure that they're level to the floor. Also remember to have the concrete guys leave the 1/4 - 1/2" for the plaster.I know you're getting it done this week, if you have more emergency questions that I can help with, pm me and I'll prioritize it - I don't get to come here every day at this time of year, but I'll make a point of at least checking my pm's, just in case you ned some info