The engine access is inside the driver compartment and the engine cover was off and the sun roof was slightly ajar while it rained for several hours. there isnt toomuch water on the distributor cap. If i let it dry out before running will this be enough?

If you're just worried about the distributor cap, buy a new one. Distributor caps don't cost that much. If you can dry it enough to make the engine run, I would run to the local auto parts store and buy a new one.

You should be OK. When you drive in the rain, a significant amount of water will get all over the engine and do no harm at all. If it starts and runs OK, you don't need to do anything at all.

You can dry things off with a hair dryer if you wish. Use a medium or low heat setting and high airflow setting so you don't damage anything.

You're likely to have more trouble with the interior of the van getting soaked. Carpeting and upholstery take forever to dry properly and mould can start to grow if you don't get it dried out quickly.

Water on the outside of a dist.cap isn't a worry it's what is on the inside that counts.Take a can of WD-40 and spray the inside if you see moisture in the cap and it will take care of the problem(I never understood this as it just puts more liquid in the cap but it works)