ORIGINAL: crispyspa
Wood boxes will work, but you have to seal them with epoxy inside and out before installation. The thing you have to remember, unless you use pushrods and seal them with a boot, water ALWAYS has a way of getting in, usually through the control cables. Best thing to so is use a balloon around your RX and pack the voids in the box with paper towel.
I agree with all of this except, I have had bad luck with the balloon trapping moister, that can get in from around the wires. Using the gold-n-rod packed with a marine grease will stop water from getting into the box. Boots work great with hard push rod set ups, just have to make sure not to make the exit hole in the boot too large.