We can have the same sort of problem with boats moored here in Puget Sound all year around (and think months of steady rain, lol).
To reduce/eliminate the mold problem, we use a plug in (110v) air warmer (mild heat, safe) sold for boats, and also use the boating desiccant sold in marine stores. Works pretty well. Make sure the car is closed up so that you are not trying to dry the world's atmosphere. Taking out the interior panels and seats is a good idea as well. And finally, I would use Armorall and leather treatment on what is left to have a coating on that material for the duration.
1989 Milano, Shankle Sport
1991 164S, stock
1994 164LS (~Q)
1972 Morgan 27
previously owned since 1964:
62 Morris MiniMinor 850, 67 Austin 1275 Cooper S (Downton 3/4 race), 64 Giulia Sprint GT (1st red one made), 72 Fiat 128 Sedan, 75 Alfetta Sedan, 78 Alfetta Sedan, 78 GTV, 81 GTV6, 86 GTV6
Last edited by Del; 08-11-2010 at 02:59 PM.