I have a jacuzzi tub that sits in a two step up faux marble platform.

I need to replace the spout – it is brass and the brass has corroded off about 3 inches from the spout.

The only way I can see how to get at the fixtures and replace them is by removing the riser on front facing the step. The fixtures are at the front right. There is no access from the side as it butts up against the shower stall with is also lined w the same faux marble. I removed all the caulk around the edges of the faux marble riser (which is about 13in high, and six feet long) but it won’t budge. Unfortunately when I look inside /under the unit where the pump is I see that the riser is constructed with plywood and the faux marble is probably glued to the plywood.

My question is: Can I just cut out a segment of the riser (both the plywood and fmarble) then simply replace it with a new piece of faux marble (assuming I can find a match…it’s about 20 yrs old) , or I could put the cut piece back and repair the cut with epoxy or matching caulk.

Other ideas…Any suggestions appreciated.
Thanks