1969 Formula S owners needs help with Variable Speed Windsheild wipers

Listen to Adriver. He knows what he is saying. I havent chkd my FSM yet but will.
In my opinion the motor shouldn't or wouldnt need adjusting unless someone dug into it?? OR its never been on this car before?
I didnt mention the adjustment cuz Ive never had to do that although I agree that it can be done IF need be.