Just use a torque wrench with the appropriate adapter-a1/4”ratchet should do it imho . Plenty cheaper one’s available , even the digital version.These screws should be tightened to the proper torque , on my felder that I purchased two years ago it was 5nm, I dont know if all planers are the same but I am sure if any were stripped the guarantee would be void.I have yet to purchase the torque screwdriver due to the price, would be interested if any one has purchased one.
Clive.