I personally have done four sets of the 15x7's.
The clear is very thick and looks like a challenge but in fact is VERY easy to remove with "aircraft" paint stripper.
You still might need to blast the casting surfaces but I have found that if they aren't really pitted you can clean that natural casting with the "heavy duty wheel cleaner" and a nylon scrubbing brush. It is heavy on the acid and returns it pretty close to coming out of the molds look.
The issue is going to be that every set that I have seen varies on the machine marks on the machined surfaces noticeably.
Some are almost non-existant and others are very noticeable almost like a vinyl LP record.
On my very early 67 set the machine marks were almost non-existant and I just cleaned them up with Brillo pads with the blue polish in it. The result was by contrast to the clear coated wheel, they look highly polished.
That set I highlighted with semigloss black paint on the castings which for me is easier to maintain and makes my set unique. I could care less about others criticisms of disdain.
What you need to deal with on the castings otherwise is a very negative effect that brake dust has on it. Brake dust cleaners are going to have all sorts of weird effects that I'd predict, you won't like.
The current reproductions, I have a set of those too, are kind of in the middle and you can notice them. The advantage of that set is that they are fully machined on the back of the wheel, taking out that "dumb-dump" lump that was originally cast in AND they give you enough room to clear the '68 brake calipers without screwing around with a grinder or additional wheel spacers.
You are going to get a variety of opinions as to what is "original" as far as that goes and YOU are the one that needs to make that decision as to how "polished" the machine surfaces should be BUT be prepared, no mater what you decide, it will be criticized by "knowledgeable people".
Hum, last thought. The originals machine marks are a result of the lathe being a +/- .001" tolerance. In other words, a crappy lathe.
I think that even if you redo them now on something as mundane, like a CNC Smithy 3 in 1, it is going to have tighter clearances then that so I would not expect to have the ability to reproduce the machine grooves that were created by a cheap machining process.
A finish like the previous posters 200-s wheels is as close as you are going to get to the original grooved finish. I'd consider that finish, "polished".
Caution: if you choose to follow my advice's, don't expect to get invited to anyone's barques either? That's ok though. They can grump at each other instead of me and I can stay home polishing my wheels.
