I hate working on horns, I have never been able to fix one right, not in 60 years.

I took my steering wheel off to find out why I had slop. The shaft moves with the touch. Not being able to fix it, I put the wheel back on. Now the horn blows until you remove the fuse.
Any ideas on why the horn is grounding out and how to stop this?

If it was working okay before, take the steering wheel back off and reassembly it piece by piece, checking the horn at every step. This will tell you where the problem is.

Also look for a crack in the housing that holds the horn pins, it’s combined with the turn signals. The ring portion that surrounds the steering shaft breaks easily and may be causing the pins to be out of alignment.

I just did mine. The two conductive discs might be touching somewhere. The horn cap holds my outside disc while a spring keeps it separate from the inside disc. I can attach pics if needed