Link to manual
http://ftp.ansmann.de/madrat_manual.pdf
2 bearings inside diff plate/outdrives and 2 large on the outside
2 bearings with slipper shaft
2 bearings in idler.
often the diff screw will rub on the dogbones when the car is built, there are 2/3 ways to fix it.
1 Try putting the screw in from the other side
2 grind down the screw
3 use bfast diff kit or carbide bearing assembly just like on the AE B4, pulls the screw away from the dogbone.
diff adjustment
Take the diff out of the car ensuring the motor plate, spur and slipper assembly is still attached. Tighten the slipper fully then slip 2 allen keys in the cups. Whilst holding the keys turn the spur gear and check for slippage. Tighten the diff screw as necessary until the slippage stops then tighten again about 1/8th of a turn. Untighten the slipper nut until its 1-2 threads from the end of the shaft then with the allen keys back in, check for slipper slipping. I have the slipper tension set so only firm pressure makes it slip. This may cause wheelies with faster motors but with 60-70 g weight under the servo this stops and gives me near perfect weight distribution. In fact the lead strips I use arent even glued down, the alloy servo mounts hold it in very securely. Also the bfast diff kit is really for the B4 so you get seperate carbide balls for the diff screw instead of the thrust washer. The upside of this is the diff screw is shorter and doesnt hit the cvd dogbones when the car bottoms out.
Hope it helps