The pictured Gold Cup does not look to have a factory ColtGuard finish. ColtGuard is a brushed finish, and the pictured gun appears to have a matte finish. The left side markings appear buffed off. The right dust cover has a rounded lower edge. In my opinion, the finish is not original.
There are original Series '70 Gold Cups with ColtGuard finish. I had one once (that I wish I had not sold).
plain and simple. I have to disagree.
1. first of all as I've said several times before, it's often hard to tell a finish from online pics because of several factors. lighting being the main one. it's often hard to tell an actual finish, satin nickel, electroless, hard chrome, etc because of lighting in said pics.
2. I've owned several lnk nib gold cups, aces, commanders, and gov. models in original boxes with the custom shop labels that I bought from a time way before people were faking those things. sold a few and still have a few. for whatever reason the markings were/are often buffed looking just like the one in the pics above. why I don't know but I do know that the colts I'm talking about were all nib from the colt custom shop.
3. having said the above, because I'm looking at pics instead of holding it in my hand in person I won't verify whether the pictured gun is legit or not, but I do know from personal experience that your comments aren't necessarily proof to say it's not original factory.
4. that gun may very well be refinished, but imo a true judgement can't be made without in the very least better pics but the real way I would know is if I had it in my hand and saw the box it was shipped in.