Couple of questions...the drain pipe for my toilet is 3.25" O.D. and the flange I have is a 4X3 (3.5" ? I.D.) , do I have the wrong size ? Also, should the drain pipe be cut flush with floor or slightly above? When drain pipe was roughed in, the plumber chipped the concrete away to allow for an outside flange but I was wondering if inside flange is better or is this a non-issue / personal preference? thanx for all replies.