I'm not 100% sure if Floquil railroad colors are actually real "lacquer". I think so, because if applied too heavily it will craze styrene. Plus it dries almost instantly when airbrushed. Anyways, it works for me and it does dry, although slowly on the tires. This may all be a moot pint, as I have heard that Floquil has discontinued this line of paints due to some stupid EPA law or something. Glad I have quite a stockpile of it!
I tried a highly recommended brand of white gel pen once... Talk about something that would never dry!
I have used Floquil for railroading modeling LOVE the stuff, BUT they are true Lacquer paints, I thin them with pure Lacquer thinner for spraying when needed, so.....
As far as Gel Pens go, I haven't heard which works best, BUT I have heard you have to be careful which one to pick as some are almost "ink" based, what that consists of, I'm not sure, I haven't looked into it that far to date.... There are several different types of them!
I have used Acrylics tho, paint and they dry just fine, BUT to wonder if a type of "Gel Pen" exists to try.....Make application a bunch more easy to do!
I have heard and seen the "Future" Floor shine and it can be sprayed onto the tire and let to dry, its also clear acrylic, and then the lacquer over that once dry and it too dries.....SO....Spraying it, is easy too, cleans up with water, and does NOT needed thinned for what I have read, and a bottle goes a LONG ways as a little really enough, don't need to "coat" things like if ya would with paint "clears"......
Sharpie poster board "paint" markers I bet would also work!