Any power lock for a Dana 70 with 35 spline will work. 3:54 to 456 ratio is the one you want. The 3:07 uses the same carrier as the 3:54's do. You could even use a 35 spline ARB air locker if you wanted.
Its best to pull an axle to make sure if it is 35 spline. You never know about Dana corp.
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93 W350 w/duals, fuel pin turned, 6X.018" injectors, 4" exhaust, 3" air intake horn, Super HX40/16, auto, 3:07's axles, 2" skyjacker lift, B&W flatbed