IMO... Ceramic diff balls and a B4 or xxx cr spur gear and slipper pads... The kit idler gears are ok to start with, the reason they strip is down to the kit slipper pads heating up and sticking putting all the strain on the gears... My standard idlers lasted me a good 3 or 4 months... They only we t because the slipper pads locked up.
Kit screws are ok, just be careful with them, stainless ones are a good option though...
