Nardi wheel adapter question

Hi guys, I bought a nardi wheel sometime ago, and found out the adapter was set up for a 74+ 911. With a little spare time on my hands, I commenced to make a wheel hub from the old steering wheel(71) I had. It worked well except for the fact that I could not wire the horn buttons up, and would have to make an external mounted one.
My question is if the Nardi hub adapter for the pre 74 911 have something on them to make the original horn ring work..??????
I really don't want an odd looking horn button sitting below the steering wheel.

Thanks in advance for all your knowledge.
S in VA