Plymouth Reliant '88 windshield arm

Good morning,

how can I remove the windshield arm from the pilot side, as it thunders and stop moving. Try to remove it but it has no lid like the others that is removed and the nut is seen, or is it only taken for a pressure? Someone can help me.

I also need the motor manual to see if I can ring it myself, since I am unemployed.

Plymouth Reliant 1988
Motor 2.2
4 cylinders

greetings and good day. Thanks for the help you can give me.