Looks like the major difference (other than the M&P roll marks on the slide) Is just the lack of the laser. I have tried to contact S&W about this trying to see if you can purchase the plastic part of the frame but was told they do not sell the frame. Thought that the frame was the metal part, not the plastic. Any thoughts about making this work, is it possible and how can you find the plastic frame to buy it?
I do not believe the Bodyguard series (either model) is modular. If you have a standard laser equipped BG you will probably need to sell it or trade it in on a new M&P BG if you want to go without the laser.