I found this and did it today. We'll see how it works out. I thought this was pretty cool. I put some silicone around my power button too.

 

Too much effort, I just use a clear sandwich bag and rubber band... w/GPS on my bike for over 12 years, still working fine.

BTW, I'd get off the bike long before the weather get as bad as a hose spraying rain on my dash... I'm pretty sure anyone with some common sense would, too.

 

Pretty cool idea. Nice an clean look. Thanks for taking the time to post.

 

Yep, I'm sure that works, but this looks better and you don't have to pullover to put a bag on it. I would also bet that the 5 minutes it took to do this is shorter than all the combined time it's taken you to pull over and get your bag out.