I would suggest going with the Steeda Underdrive Pulleys.
I made the mistake of ordering the BBK Pulleys, don't get me wrong I think BBK makes great products for the older Stangs, but for the newer models 99+, I think they got a little lazy. With the Steeda Pulleys you won't have to piggyback off your stock crank pulley as you would have to do with the BBK set.
Anyways let us know how it goes.
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Yours in SPEED=======
Mandy aka GTGRL00
2000 Mustang GT