More precisely, it's NOT a Series 80. Most Series 80 parts, such as grip safeties and extractors, will fit and work on non-S80 guns.
The beavertail grip safety, as popular as it is, is one of the most misunderstood "1911" parts on the market. The Mil-Spec frame must be cut and contoured to install a beavertail, and you want to get the right part, or you won't get a good fit.
The S&A grip safety which requires cutting the frame with a .220" radius is designed specifically for the Mil-Spec frame, and will fit better than any of the more popular .250"-radius beavertails.
Triggers will usually need a little bit of file work to fit, as they are usually slightly oversize for a within-spec pistol.
The thumb safety will almost certainly need a bit of file work to fit, as they are also sligthly oversize.
Sighting options are almost limitless, but the Mil-Spec sights are really quite good. I removed the white dots from the rear sight on mine, and the resulting sight picture was better than some aftermarket sight sets that require milling new dovetails in the slide.
Get quality parts the first time, and that will save headaches in the long run.