Unless you are a dedicated bulls-eye shooter, adjustable sights on a 1911 are completely unnecessary.
Fixed sights are much sturdier and, if properly regulated, just as accurate.
If your pistol's fixed sights are zeroed at 25 yards, your pistol is properly regulated for practical self-defense shooting at any distance between its muzzle and 50 yards.
It will be much more intrinsically accurate than you are.
Night sights are a nice gimmick, but also completely unnecessary. Indeed, in very low light they can be a serious distraction, rivetting your focus on the sights when you should be fixing your gaze on the Bad Guy.
If the light is so low that you can't see your sights, how do you know at whom you're shooting?
Better than night sights is a good flashlight, and some training in how to use it properly.
If you are still intent upon adding adjustable sights to your 1911, let a good gunsmith do the job. It is not a kitchen-table-gunsmithing sort of thing.
The slot into which the sight fits is called a "dovetail," and any decent gunsmith will know the correct size, and how to fit and regulate the sights.
Grips? Google "1911 custom grips," or look at this location: http://www.esmeralda.cc/