I purchased a Maax ABS shower kit and it includes a "Wedge-lock no-caulk" drain assembly. The instructions indicate that the drain pipe needs to be 1/2" below the bottom of the base. The problem is that the bottom of the base at the drain hole measures only 1/4" to the concrete basement floor. I have already chiseled out a 5" diameter, 2" inch deep trench in the concrete around the drain pipe to accomodate the drain assembly. But how can I cut the ABS drain pipe 1/4" below the level of the floor?