The cover plate gets stuck on from years of use my 71n also has a sticky cover plate. If you have a vise with soft jaws put the square drive in the vise and tighten down fairly hard on the square drive and rock the ratchet up and down. But if you don't have a vise with soft jaws take the screws and put them in through the back and take a pair of pliers and pull on the screws a little at a time and it should pop right off. and it should be pretty tough the first time you take it off. And if the ratchet is pretty beat up and rusted just clamp it in a vise and use a punch and knock on the gear through the back towards the cover plate and it will come out but will ding up the ratchet. I hope this helps.
