Glock 17

Note the magazine has a small part on the back, it is a rubber piece to ensure the mag will not drop out from the gun easily

The tac light is removable.  It is hollow inside with a small hole on the back, meaning that putting a small light bulb with a thin wire coming out from the back is workable, but u need to take off that clear plastic cover first.
  



Colt   Peace Maker
The only workable part of the Colt Peace Maker is the cyliner.  The grips are made of plastic.