I am installing a Stebel Compact Nautilus on my '06 1200GS. I'm using the OEM horn to trigger a relay which is powered directly from the battery. The Stebel will be installed near the spot where the OEM horn was, i.e., in front of forks and behind the oil cooler...up high. I need to add a ground wire nearby. There appears to be a good candidate close by...here's a pic.
Is this a good choice? Should I somehow prep the bolt or the surface below (like sand it to bare metal??)?