Minwax Polycrylic on the wood, applied VERY sparingly for the first coat.  Get one or two full coats on, fully dry and sanded between coats, then put on silkspan and sand.  You can seal with just Polycrylic, or Polycrylic with talc -- but if you add too much talc you'll have adhesion problems; just enough to make it sand easily is probably wise, and be sure to go over it with fresh sharp sand paper before the top coat.

Top that with Rustoleum Gloss Protective Enamel from a spray-bomb or from a quart can if you have spray equipment.  It's actually not that bad brushed, using acetone or possibly enamel reducer as a thinner (acetone dries very fast).  Be easy on the stuff -- it's easy to really lard it on, which shows up in the plane weight (I have a lot of heavy planes).

Cover open structures with 'coat (Mono- or Ultra-).  If you start with very clean 'coat you can do trim with the same Rustoleum.  It sticks even better if you take some copper or steel wool and scuff up the coat where you're going to paint.

As long as you cover all the Polycrylic it'll be fuel proof, so when one of your slime-powered buddies accidentally spills fuel on your finish or coats your plane with exhaust fog you won't have any finish problems.  Edit: if, that is, you let the paint cure for two weeks before you splash it with fuel.

I'm on Year 2 of a Fancherized Twister that I painted this way, and my only big problem is that one of the trim colors was painted a week after I painted the base coat, and it's got adhesion problems.  This is the only time I've had problems, and also the only time that I've painted trim more than 48 hours after I painted base.  So next time I do that, I'll scuff up the base coat.

http://stunthanger.com/smf/index.php/topic,30238.0.html

The lettering here is vinyl, everything else is 'coat and paint.



With vinyl graphics added to the tail:



Lettering on wing is Monocoat, all the rest of the red is Rustoleum.  Rustoleum white on the fuse, 'coat on the wing:

You can also go with water based paint like http://www.autoaircolors.com/ and use a polyurethane topcoat. Either single stage or two stage.

Hoovie,

On AutoAirColors:

It can be a pain to get to dry sometimes. If you live in a humid area, better get out your hair dryer or be willing to wait awhile between coats. It does have an intercoat system that allows you to seal stuff between trim colors but the stuff takes some learned skills to get it to work well.

I doubt that I will try the auto colors since I have no wish to use anything that does not come in a spray can...
A 14 foot trailer means limited tools and storage...

If you're building models in it, it means a serious dedication to the sport!