Sell it. Eventually someone will want to re-gear (up or down) to 3.73's and it's super easy to swap diffs compared to re-gearing. Post on every ranger and explorer site (explorer-forum.com for one).
You may not get much for it but eventually someone will probably bite.
It also makes a good case for someone to re-gear it out of the truck. Someone can buy it, drop it off at the gear shop (cheaper than having them remove it), get it re-geared and swap it in when they have time, and sell their old front diff. Saves time/money and prevents the truck being down for longer than it needs to be.
2006 F150 FX4 Super Crew - Bilstien 5100s leveled 2", 35" KM2s, 4.56 gears, Detroit locker, Eaton E-Locker, Traction Bars, AEM intake, Xcal 2
2010 VW Golf TDI 6MT