Information and concerns with Full Floating Axle Kits #41, #44 Taper axle, and #44 Flanged axle rearends share a common part. This part is called a centering block. This is located in an open carrier and some differential lockers. These centering blocks are necessary in order to adjust axle end play on these differentials these centering blocks may have to be changed in order to install the full floating axles, otherwise it will prevent the axles from being in the housing far enough. Spyder gears may have to be changed in the early differentials if they are 10 spline.
I recommend a Spicer Powerlok for a locker as they will a certain amount of slippage while still locking up quite well. WARNING: A gear drive locker without discs is very positive and can cause axle failure when Jeeps are operated on hard surfaces. Cornering is the cause of a tremendous amount of stress. This can cause the splines to twist or the axle to break.