Once you get it off, just unplug the connector.
Then you can push the inside of the pad back out so that it's flat like it's supposed to be.
Mine did the same thing after I got my 89. I ordered a replacement pad ($30 used). When I got it in, i noticed it was flat. Mine was very concave from years of the PO leaning into the horn and bending the soft metal behind the pad.
Steve