I used my heat gun to soften the tape, holding the reflector in, then pried it out with a small flat bladed screwdriver. I padded the edge (pry point) with a couple of layers of duct tape. That worked pretty well but it was really hot. I removed the residual tape pieces with 'Goof Off'. Getting all traces of the tape out was the hardest/messiest part.
Do you care if the reflector is damaged? I removed mine and wasn't replacing them, I just used a small screwdriver that I put some masking tape on and pried it out. Broke one, one came out fine, and I promptly threw them both away.
Cleaned the inside with some Goof Off to get the adhesive out.