Ah yes, I bet you are right about the "pin" being the spring. When I took the belt off, I used a pair of channelocks and grabbed the end of the tensioner, (opposite the pulley side) and twisted it clockwise until there was enough slack to pull the belt off the alternator. When I put it back on (and subsequently put the new belt on as well) I only needed to torque the tensioner about 1/4 inch and the belt slipped on. When I let go of the tensioner, it basically came back to the stop and is barely putting tension on the belt. I should have marked where the tensioner was positioned before I took the belt off so I'd have a better idea of what's going on. :P

What do you mean by pre-tension the belt?
P.S. I've installed probably a dozen serpentine belts on five or six different cars before and have never had this kind of problem. :P

Thanks,
Brendan