problem with bbk underdrive pulleys

i was putting my book underdrive pulleys on today and i got the one on the crank fine and the one on the water pump was fine also but i went to put the one on the alternator and the bolt the hold the pulley wasn't long enough! now it's not the factory alternator so i was wondering if that might have something to do with it? has anybody ever had this problem before?

thanks to all who reply!!!!

The factory alternator pulley has a spacer behind it, the BBK pulley may not need it. Also check to make sure you're putting it on the right way.

Having a replacement alternator shouldn't make a difference.....I'd be very surprised to find a 3rd gen that still had the original.

ttt

did you try the spacer behind alt like TheGreatJ said? that sounds like the only reasonable answer.

yeah i tried taking the spacer off but there is both a nut and a washer i can fit the nut just barely but the washer wont go on, and i think thats a locking washer so i need that on there!!