used Tollsters method as well
I have mounted stebel horns twice using tollster's method. Although pointed left, I find the volume sufficient to scare the shit out of those pesky cagers. Simple bar stock, cut to length, drill holes, round off ends, mount. I used easternbeaver.com wiring harness each time, which makes this a simple plug and play event. The harness comes with a very reliable relay inline which eliminates the crappy relay the horn ships with. Highly recommended.