Here's how I did mine, same dish as you.
Set the motor to 0 (true south)
Put it and the dish on a PLUMB pole.
Used a compass and pointed it best I could to TRUE south (magnetic + - deviation- look at a map.)
Commanded the dish to move to my true south sat (also AMC5).
Now here's the important part- I used the receiver, and a Lyngsat chart of the AMC bird, and manually put in a transponder I figured was active and strong.
I then moved the dish up and down, looking for signal. I moved the whole motor/dish assy CCW or CW on the pole as I moved the dish up and down SLOWLY.
I ignored the dish setting scale. I just was patient.
I suspect you are depending on an inaccurate scale, and sweeping across the sky until AMC9 comes in.
When I got a lock, I snugged the bolts on the dish, and pole, and blindscanned the bird.
Then I spent the next 3 or 4 sessions tweeking up/down left/right until I can track the arc well. I can get everything except one major transponder on
IA5, and 80cm is a little too small for good quality there. You really have to be accurate with a small dish like that. My 1m fixed gets things much stronger, and is actually easier to point. Shame that motors cost $100 for that big boy.
Larry