I had a 1994 and when I started having trouble with it, I replaced all of the plugs and the relay.  The relay was actually ok, and the plugs seemed ok when I took them out, but apparently at least one of them wasn't because that fixed the problem.  Replacing the ones on the left side wasn't a problem, but a couple on the right side were a real pain.  Can't remember which one, but it took as long as the other 7 put together (of course it was about 10 degrees F, too).  Easiest access on the right side was to take the wheel off and work through the wheel well.

I never had my light not work, but for a while there it would take 2 or 3 cycles to get the truck running, even when it wasn't that cold out (50 degrees).

Good Luck,

Mike