Cleaning steering wheel horn buttons

I have a 1967 Sport Fury convertible that has a 3 spoke wheel. each spoke has a horn button and 1 of the buttons doesn't work at all and the other 2 are intermittent. They did not work either until I kept pushing them. now they only work in certain spots. If I ground the horn ring in the center of the wheel the horn works great.
How do I remove the buttons off of the wheel so I can clean the electrical contacts beneath the buttons? am currently trying to get electrical contact cleaner to...

Cleaning steering wheel horn buttons
Author: 67 ragtop