Update:
Well, nearly six months later.....I finally got my tactical light mount...
Unfortunately, Since a new G&P M500 is in the upper $100 I decided to go with something cheaper. I felt I made a good choice though. after surfing real firearm forums, all the hype goes to the "front sight mount" I found one made for the real thing and I bought it for $25. It has 4 slot rails on both sides of the front sight post. For the tactical light I have on, it's a Streamlight TLR-1 I took off my Glock 22.
Before:
After:
Since I need the TLR-1 for the Glock, I'll be replacing it with a Surefire G2L soon. Next thing to do is to paint the flash hider black.