Since it is on a Blazer, maybe consider rewiring it and moving the wiring inside. I did my Blazer a couple years ago, and it was well worth the time invested. This eliminates the water issues, snag issues and other problems associated with wiring running under the vehicle. I think I have a complete write up in my blog here on CK5, and I am more than willing to answer any questions you may have. It also makes it much easier to troubleshoot trailer wiring, but that was just a bonus for me, I absolutely hate having wiring underneath a vehicle that has a solid body all the way to the tail lights.
