Your IFS front end is not very fond of "Lockers" (Detroit, ARB, OX). Manual locking hubs (Warn, Superwinch) are a different animal all together than a "Locker". A locker is installed in the differential, and engages both axle shafts to spin as one. Manual locking hubs are generally used on a straight axle 4x4 and engage the wheel hub to the axle shaft. Even though you may have a locking hub on both wheels, unless you have a locker in the diff you'll still send power to the wheel with less traction. With an IFS front end like you have, your best bet is a limited slip differential. Less stress and more traction than you currently have.
Hope this helps.
G.