Yep, just a bath. Then lightly grease, not oil, the slide rails. There is no 'best' anything. Hoppe's or any other brand will do.
Don't worry about an 80 vs 70 series Gold Cup. It's still a high end target pistol.
You need to take your da out for a really nice dinner at the very least.
Stole this from another forum.
"When the Gold Cup pistol received the Mark IV Series '70 roll mark in 1970, the Accurizor barrel and collet barrel bushing were installed. In 1983, Colt started making the Series '80 pistols with the firing pin safety. From 1983 to 1988, the pistols kept the Accurizor barrel and collet bushing. In 1988, the Accurizor barrel and collet barrel bushing were replaced with the standard parts.
Later, Colt eliminated the steel "kidney" cut out GCNM trigger and replaced it with a three-hole trigger. At the same time, the sear depressor and sear depressor spring were eliminated. "Enhanced" Gold Cups were offered with the elongated Commander hammer. Even later, Colt dropped the GCNM and introduced the Gold Cup Trophy, which is also a Series '80 pistol.
Some of the early Series '70 GCNM guns had lightened slides and the extractors are visible through the underside of the slide. These guns need to be fed lighter loads to avoid the possibility of cracking the slide, especially near the breech face."
