So you need to chill... Not everyone is on the Site 24/7, well maybe a few are ;D
There must be a 100 threads on doing an Explorer front dress swap... I don't recall that anyone has suggested using the pulley you have brought forward.
Maybe someone will chime in about their experiences soon, or not?
You might be the guy that has to buy it and do the test fitting for the rest of us. By the way, we all appreciate those folks who take the time to do stuff like that.
The WH's part, will not work because it is for a 3 bolt HB and yours is a 4.
Right now that leaves spending the 191.00 for a known part that has worked here for many of us or buying the unknown pulley that could need to be shimmed to line up. It might be the wrong diameter? Does it center itself by the center hole or by the bolt holes. No one wants a wobbly HB pulley, that will create other problems.
How new is your HB? How many miles on it? More than likely it is a two piece with rubber bonding in the center that is getting old... It might be time to replace it?
Sometimes it is not about the cost... But about how much extra work is created.