The new pistols are for the most part dead ringers for the original guns; however there are a few differences. As already mentioned the new guns use the solid barrel bushing, whereas the 1st Gen. guns used the collet bushing. Both lack the Series 80 firing pin safety, however the new pistols do use the same internal parts as the Series 80 pistols. In other words, the extractor, firing pin, and grip safety have the notches cut into them that would normally allow the FPS parts to function. There are however no cutouts in either the slide or the frame for the levers and plunger, which means that a firing pin safety cannot be retrofitted to these guns without making the additional machining passes that a Series 80 gun requires. This all may sound like a cheap cop-out at first, but one must look at it from a manufacturing standpoint. Series 80 parts are fully backwards compatible in Series 70 guns, as the "notched" parts do not affect function and aren't even noticeable when the gun is completely assembled. In the name of streamlining its spare parts network Colt dropped all of the older Series 70 parts from production many years ago, and existing owners of older pistols are merely expected to order S80-type replacement parts which of course will still work fine. There was simply no point in making these older parts all over again just for a limited-production Custom Shop item, and so the new Series 70 guns use the exact same internal parts as the other current pistols in Colt's product line. It is worth mentioning that Colt did the exact same thing with the WW2 repro M1911A1, meaning that model uses S80-type internal parts as well.
