Yes, he certainly could!
I purchased my M1014 with the Sidearmor already installed--it's one of the things that caught my eye in the first place. The fit is great--it leaves enough room to remove the barrel without any hassle. I can't comment if you need Locktite or not because I didn't install it. At any rate, Locktite or no, it's still as solid as the day I bought it. It works great for a flashlight attachment method--it puts my Surefire M3right there at the tip of the gun. Utility wise, it'll work great for a flashlight or laser. If you're looking for just the flashlight mount, then the sidearmor is a good choice. However, if you want more of a rail system that will allow for a vertical grip, wait for the FCAM. Anyway, I really like mine and am glad it's on my shotty.