steering column issues

[70Custom10Nut]

I've asked before, does the spring on the top end of the steering column go on under the canceling cam or on top? I'm dealing with an aftermarket steering wheel hub that worked well on my non-tilt column, but doesn't seem to go on far enough. I have already made sure that it is seated and adjusted where it's supposed to be. Also, how do I get the horn contact plunger out so I can replace a weak spring? Does it require a special tool? Any advice would be great. Thanks, Cnut