Best thing is to set up on the Thor satellite.
Make sure your mount is perfectly vertical as you look from the front and the sides.
Then set your latitude on motor, then set dish inclination , Now you should be able to get a strong signal on Thor by adjusting slightly the dish inclination and possibly even twitching the latidude setting on motor.
Either way, once you get your strongest signal on Thor, then tighten the mounts and ensure that as you tighten, you still have the strongest signal.
After this, you must remember that you are just west of south, so if you are using the goto function to go to a particular satellite, you will not be exactly on that satellite and you will require some fine tuning.
On my system, i used the goto function, then used the step function to make 1 degree steps east or west of each satellite that i was tuning and this allowed me to get great signals on all satellites that i required. I had to individually tune every satellite for the optimum signal, and 1 degree can make a big difference on signal strenghth