When Leanna did my slant and Poly valve covers in a custom finish, I had her mask the top of the stovepipes as per originally done. We also discussed the same procedure on the Commando valve covers (my sets of Commandos were done before she started masking the top of the stopepipes..
I discussed original versus Leanna's finish on Commando valve covers with both her and Ulf (65Dartcharger). From what I've seen it appears that some original Commandos I have owned had a slightly more "wrinkly" finish and others a sort of smooth wrinkle finish and varies from valve cover to valve cover. This was probably due to the type wrinkle paint that was used, curing time, the person painting the valve covers, temp when done, etc. The valve covers Leanna has done for me falls in-between these two. As I told Ulf, I wanted a wrinkle finish that was maintenance free and the powder coated ones certainly are maintenance free - wipe them off and they look just like new and are not affected by the heat of the engine. With the restoration he's doing, he wants a factory style finish and feels the powder coated finish won't provide that.