Thought I would share my today project.
I pulled my bumper off and unbolted the horns from the brakes (and removed the brackets) that held them. I took the horn and direct mounted on the inside of the sub frame int he center in some existing "pill" shaped holes as you can see in the photos. Then I simply made up a small wire with one end a prong and the other a clip. Hooked them up - tested - taped for good measure. Done.
Still sound loud and nice and out of the way.

 

Now you just need to relocate the vacuum ball.

 

Next on the list... Just need some vac tubing and a connector.

 

Hmm, the existing tubing on mine was plenty long to move it into the engine bay... since the hose starts in the engine bay and all.

 

To be honest I didnt even check to see how much lien I had to work with. Will do that.