How do you guys do this?

No, I don't want to just walk around the got "bang" in the head just because I ruined someone grand luxe dial or something. 😉 It's for the sake of "science", I guess I could called it that way? Who knows if anyone working in chemical industry reading this thread would led to the establishment of a chemical product specific for watch dials, like polywatch. Ey, it's a good business plan y'know... 😁
As for me, I don't want a shitty watch so I don't want to give the customer the same either... Even I diligently ask the admin about what should I limit myself to what my customers asks/requests as case polishing and hand exchange are mostly included in the service when it came to vintage watches that enter our workshop.
Though I think I'll do more experiments with scraps dial 😁

Yeah, to keep up the appearance 😁

Yes, I've done it in cheap seiko dials for research. Haven't found a cheap omega dials from 40-60s to work with. 🙁

What do you mean by not terribly vintage sensitive?
You mean those kind service center that treat the vintage ones and new ones the same? Just change everything new like that beside the movement part? No, we're not, as I was offering myself to do all the vintages that came to the office, I ask the frontliner and admin about the notes that the customer gave before executing the watch. In the early month, one would protest about why don't we change the old hands to the new one and done the polishing, one would protest why did we put new hands and done polishing. Eversince then we always ask them for the watches prior to 90es. Even if we had to do polishing, I just had to follow how does it look in the catalogue then proceed to do the watch. I worked in SGID Service Center together with my juniors from the school, all of them WOSTEP and OWME certified, before they were closed last year in March, now it's been taken over by the local Omega AD and one of my junior is there together with my one colleague, but I don't know how the procedure now. I worked with one other local AD together with my other two juniors afterwards but I had things that's not sit right with me when I was working there so I resigned. Nowadays I'm just occasionally helping my seller friends in my local watch community to my best abilities and done the same discipline I've learned back in school and the office while applying for SGUS NJ this year but too bad the outbreaks happened 😲

Yep... Cz most of the customers ask for them and cz it's free (unless if the hands made out of gold, had additional cost, but for polishing is free) and the locals here like freebies... But we ask first and told them whether the customer wanna do that or not. Though even we exchange them we returned the original packed neat and tight.

if you use a lemon solution to clean a dial it will remove the old varnish , it can also remove the printings, as Archer said it dépends how the dial was built and how it has aged. If you succeed, you have to reapply a new varnish , there is a reason it was there at first place. If there is gold or silver markers , be carefull to hide them. I have cleaned some dial with lemon solution , I have encountered success and disasters. It is a gamble, so you should only clean a dial if you are ready to lose it. My advice , if the dial is Ok but too much aged for your personnal taste , don’t take the risk to destroy it, just sell the watch to someone who like it , and buy another one you like more.

If it doesnt bother you, leave all the marks and blemishes, adds to the character and originality, if the time comes to sell - let the new owner decide the watches fate.

Prospective dial cleaners should take a cue from the furniture restoration business. As Archer notes, you have to know what you're dealing with. The coating on a dial could be varnish, lacquer, or some other coating so treat each according to their needs. While practicing one technique on a throwaway dial may work for that brand, it's no guarantee to work on another. It's tempting to want to use what you may have around the house, but jumping right to an acidic solution can't possibly be a great idea. Work your way up slowly, using mild detergents before professional solvents or mineral spirits. It may also be better to try to simply stabilize a dial's finish, i.e. waxing, rather than trying to remove and replace a coating.