Which Tuff wheel is this?!?

That's the first one of those I've go to see under the center pad. I will recommend getting a factory type horn switch for the grant tuff wheel, it has the screw holes in it to mount them. The Grant horn button kit is junk, IMHO. There's an adapter inside the grant cap that can be pulled out to allow it to be mounted on the factory horn switch. Here it is from classic industries site.
1967-1979 Plymouth Parts | MW931 | 1968-76 Mopar Horn Contact Assembly; with Tuff Steering Wheel | Classic Industries
I would look and see if there are screw holes under that metal cone first. All you may need to outfit that wheel with a horn switch is to take the cone off, mount the horn switch, and get a Grant or a repro horn pad. These are the screw holes to look for.
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