Thanks. What specific hardware are you referring to? Actually tried to fit in TC3 differential screw to replace the Pro4's but it was a tad short in length. The Pro4 screw was not able to reach the grooves and tighten itself.
use the TC3 diff screw and the t-nut that comes with it.......build your pro4 diff with those parts....use a drop of blue thread lock on the end of the nut.
with that you should have zero problems.