You presumed correctly; I'd like nitro. Though, I do have some questions around the topic that I'd like to pose to a skilled refinisher..
The custom colors for '60 included some from the Duco line which were nitrocellulose lacquer, and some from the Lucite line which were acrylic lacquer. Most of the noise in vintage guitars is around the nitro stuff, and I have one instrument with a nitro finish that I like a lot.. but I'm curious to hear more about the acrylics. Especially because Olympic White is high on my list and it was acrylic. (which raises a lot of questions.. every oly white instrument from the era that I've seen look like they wear the same as nitro.. or maybe all the ones I've seen are just refinishes with the wrong paint)
But I guess this is why I'm looking for someone who specializes in vintage stuff specifically. I had seen some of Pat Wilkins work, and it looks high quality, but all of the examples I have seen of his look really modern, or even when it's a vintage refinish style, like s_wood's up there, it just looks new to my eye. (still looks great, just not what I'm going for!) I want to have the body done with a level of patination that matches the survivor neck. I feel like finding a vintage refinishing expert will help make those decisions about the nuance of the paint to make it match and will know which paints take what types of simulated aging.
But back to your question.. yeah, I expect someone doing a vintage resto to know how to do both nitro or poly. I mean, I've got rattle cans of nitro from re-ranch in the closet, but this is too valuable an instrument (in dollars and in memory - was my deceased uncle's) to not find a specialist for.
Have you ever read this,
Fender Custom Colors: Color Confusion?
Whether it was Duco NC or Lucite acrylic was a function of who made what color at that time. Whether either received a clear NC top coat was a function of Fender production triage/choices or rather how busy they were at the moment.
Fender used Lucite acrylic lacquer for certain colors like Olympic White and for the metallic based custom colors; Candy Apple Red for example. For CAR, Fender used Lucite silver then sprayed over that clear NC lacquer top with red tint added; or translucent red top coat.
When Fender sprayed Olympic White, a Lucite color, they may or may not have sprayed a NC top coat, depending again on how busy they were. Examples of '60s Oly White Fenders with and without top coat exist. This is covered in the above in depth article. Whether the Oly White was oversprayed with NC top coat would largely factor in how the finish aged or yellowed; thus a large part of observable variability you may be referring to. Plus there's small variability in formulations of NC lacquers and solvent combinations--chemistry--that contribute to how finishes age differently over time. No doubt there are plenty of Oly White refins in the wild done myriad slightly different ways, too.
There's plenty of random elements involved.
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On the matter of whom use.
Pat Wilkins doesn't do Nitro. Independent guitar finish shops that do nitro vs those who use polyurethane generally tend to stay firmly in one lane or the other, instead of working with both.
MJT and Starr do what you're looking for, as mentioned above. I'm sure there are a few others; I'd have to google that to recall.
MJT offers degrees of aging or relcing. Their 'closet clean' is the closest to what you seem to be seeking. You should look at their site online. They show lots visual/images regarding color, degree of fading, checking, relecing, etc to choose from.
An example of closet clean Oly White from MJT.
