I know nothing and need help for my 85 RX-7

[Ben Wadler]

Looking for technical help on a couple of issues for my 1985 RX-7 that my son and i are bringing back to like.

1. The rear wiper goes up when turned on but doesn't stop on the way back down. Feels like you could spin the blade 360 degrees?
1a. How do i take the motor assembly apart without breaking anything else?

2. The buttons that direct the air flow inside the car from defrost to vent to floor does not work. Local Mazda dealer say there is a part broken behind the dash but it can not be bought.

Once we figure out what the parts are where can we purchase them