I am in the middle of putting in a shower pan where a tub use to be. I have had to jackhammer for the plumbing and its not been fun. The problem now is that my plumbing job is 1/2" too high. It's all cut and glued. I am installing an Oatey 42150 and I need to raise it. I wish they made the same unit that wasn't so tall. Right now I just want to put plywood over the cement to raise the pan up and I'm good. Is there any issue with that or are there any precautions/prep work to be done? I don't want to redo the plumbing because its already resting on concrete and that would mean a load of work. My slab seems to go on forever. I am literally digging a hole in concrete. Thank you.