What pulley is that? Something in addition to what is there already? Do you already have your Explorer setup installed, or is this all going to happen at the same time?
Only thing some people run into that I can think of is a clearance issue with the lower passenger idler pulley and/or bracket hitting the frame crossmember. But that's only in about 20% of the cases it seems, so I wouldn't necessary start cutting just yet.
If the engine is installed, it's easy enough to mount the bracket to see if you have clearance.
And speaking of clearance Clarence, without a body lift the power steering reservoir will often have to be relocated down and over a bit.
I'm sure someone knows of other things, and sorry if I misunderstood your question about a particular pulley too.
Good luck.
Paul