How do I install a fiberglass shower unit on a basement cement floor? The drain is flush with the floor. Do I raise the floor to make room for the plumbing hardware, or do I cut into the floor to drop the hardware into it?

Please explain;
The drain is flush with the floor. What drain? Is that a floor drain you're referring to?

Do I raise the floor to make room for the plumbing hardware, or do I cut into the floor to drop the
If there's nothing there you must open up the floor over to the main and cut in a branch line for your shower. This line must have a trap and raiser positioned where the shower base drain will be. In addition a vent will have to be installed just downstream of the trap that will run out the roof or revent back into a existing dry vent.. As long as the floor's tore up why not add a lavatory on the vent line? You could even add a toilet and make it a basement bathroom if you wish. Good luck, Tom

First, see if you have trap installed in the concrete. Take a bucket with water, pour it into the pipe and see if it drain. Then, when you look inside, there should be standing water on the bottom of the pipe.