I used stainless tig weld wire. Wrapped it around 1-1/2 tubing 3times. Used a short peice of 1-1/2 schedule 80 pvc. Machined inside slightly to fit over column. The contact plate inside wheel is stainless light gauge sheet metal. Made a few isolation washers out of plastic containers. Drilled a small hole through wheel for wire to go amd make contact to plate and spring. Cut hole in p5 Center cap and silicon the new 2in horn button in. Purchased horn button and wolo horn off amazon. Wired through std 12 v relay same as most cars.
I can send more pics and info if you wanna try it.
I love having the horn on the wheel. Will try to upload a video shortly.
Cheers