Full Conceal had a prototype of their concept back at SHOT Show 2017. Pete posted about it here. Their original concept was a cut down Glock frame and the remaining grip/magazine would lock onto the frame making the pistol a rectangular brick. You would have to remove the grip/magazine and insert it into the gun to make it into a complete pistol.You'll have to visit The Firearm Blog to see the pictures (and also a very short video) demonstrating the concept. Personally, I'm a 1911 Slob Snob so I try not to show Glock pictures here .... even when they look like a Klein bottle as an Embryo, or something that came out WRONG in the Starship Enterprise Transport Bay 3.
Or ... like this: