simple fix to stop driveshaft pins coming out:
im not 100% sure on bearing size,i think its a 10mm outer but measure your driveshafts to double check.
take the above bearing,dremmel across the outer ring so it becomes a split ring,then push the internals out.
pushfit the split ring over the driveshaft and over the pin area,its a very snug fit on the shaft and the pins wont now come out,you can pop them back off when needed to check the pins for wear.
check the driveshaft moves free after fitting because if the pins are too long they will rub on the inside of the split ring and may bind it..2 secs with dremel on the pin cures it.
if you use old bearings even better as the groove inside the bearing is deeper and this wont bind on the pin,im sure its either a 10 or 11mm external bearing we used but they work perfect.
its something we do on the 1/8th d8 buggy(see pic below) and we did this to bruces and craigs durango,no more pins coming loose eh craig
dave