I can't say for certain, as I have not held it in my hand, but all the FCUs should be the same. However you'll have to also install the Trigger Bar from the M17 as it's cut away on the MS version.
Yes, you can fit the manual safety, but it’s more involved than just swapping the trigger bar. Besides the additional parts (Left paddle, Right paddle, safety detent, detent spring) You’ll need to have the frame cut to accept the safety paddle. AB Prototype offers this service
I wouldn't try converting the FCU, however you CAN build up an FCU for a model with safety, notch an x-5 frame, and put the x-5 slide on it to the best of my knowledge. I've seen at least 1 done up that way.
A forum community dedicated to SIG Sauer Pistols and SIG Sauer Rifles owners and enthusiasts. Come join the discussion about optics, hunting, gunsmithing, styles, reviews, accessories, classifieds, and more!