astrodanco said:
Good for you, that's the prudent way to do it. I cringe as I read about people cutting holes in their brake lights and allowing water to get inside. I have three NMO mounts on my car. One for the GPS antenna, one for the cell phone antenna and one for the scanner antenna. I'd have one for the XM antenna too if I could find an NMO mount XM antenna.
If done correctly, no water can get inside. Now don't get me wrong, when you cut corners, ANYTHING can go wrong. But, when I done my truck, I just took my time with a dremel tool, and whittled and nipped until the coax fit very snug into it's "notch". I also took a small dab of clear silicone caulk, and dabbed INSIDE the brake light, to prevent any water that might get in, from getting in.
An ounce of prevention is worth a pound of cure.
I am very satisfied witht is setup, but I understand what you mean about the water getting in. It would/could make for a very unpleasant situation in a downpour..
Honestly, If I could do over, I'd go with an NMO mount. I had no idea I was going to leave a radio in this truck for as long as I have, and if I could do over, I wouldn't think twice about popping a hole in the cab. an NMO mount really makes for a cleaner install also.