Thought I'd throw it out here and see if anyone else has run into this before I start pulling the steering wheel apart. For some reason the turn signals on my '65 Bel Air (Did I say '65? I meant '64, yeah.... '64 ) will work fine for about 2-3 weeks, then they won't work for about 2-3 weeks, then they just start working again. I would think if it was just a loose wire somewhere it would be a lot more random than that, rather than working or not working for weeks at a time. Anybody know offhand why they might behave like that?
Pull apart the connections at the firewall and clean um up, unbolt the fuse box and you will see what I'm talking about.
also look at the fuse box itself, the contacts that hold the fuses get loose/corroded. Probably that connector though.