[Jim Vander Wal]

Holes in the floor, they call these "drains".
Tonneau cover when parked. But always park front end higher than rear. The rear fenders and deck will divert all the water into the interior.
Tires that work in the rain, this is the difference between driving and the ditch. TireRack reviews are generally very good.
Waterproof covers for anything you don't want to get wet. GPS units generally don't like water, gauges don't either but not much you can do here.
I've run tops, better but as Bob indicated "not as wet". A Cobra top is some weird cross between a WWII military pup tent and a plains Indian teepee, neither were particularly effective. Tops are for girls.
I've run the tops on two different Superformance cars and prefer to just drive faster but it still sucks when you have to stop at a traffic light.
BTW, I have hours and hundreds of miles driving in the rain. Upside is most everything dries out but it might take a few days.
If you're going to travel you're going to get wet. Smile, it's part of the adventure.
If you don't like being a "cowboy" buy a Corvette. There's noting "civilized" about a Cobra.
Jim
SPF 1855 & 2584
FFR 8885 under construction.