I know this is an old post, just cruising the site and saw it. Anyway, if you're just asking about cleaning it and trying to avoid the rinse water going into the cockpit, try this; body shop supply houses sell a spray bomb glass cleaner. Use it much the same way you would on glass, just immediately follow up with wiping it off,don't use paper towels! they have wood in them and will scratch! Just use a soft cloth. You can get soft paper polishing clothes at the supply house too. follow with a light polishing and it will look as good as if you'd done a regular hose and soapy rag wash.
I do this on mine in the shop to keep it clean. My car isn't completely done, no weather strip on, etc. so I can't really rinse it down just yet.
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