distributor cap moisture

[dcasalena]

I recently started covering the truck with a high quality cover to keep the spring sap from dripping all over her (or it, I haven't given a name yet).
After the first rain with the cover, the engine was soaked with condensation (and the body was dry). Cover worked great, but now it won't start, cranks but no fire.
I like to start with the easiest and cheapest solution first, so I'm guessing that condensation got inside the distributor cap. I've read some posts that recommend using a solvent/spray to remove the moisture from inside the cap. What do you guys recommend I use. My local Napa guys might not have a recommendation when it comes to a 40 year old system with points and a cap so I'd like to go in with an exact solvent/spray I can ask for.
Also, anything I need to do to insure everything sparks in the right sequence if I remove the cap, dry it out, and put it back on?