Your mechanical limit is the physical limit on your actuator out at the dish.
You need to press the East button while constantly watching your dish. You may have to run back and forth from the ASC1 and out to your dish till you get it where you want it.
Do all of this while you ignore the position number on the front of the ASC1.
NOTE: If your dish is moving the wrong way, for instance you are pushing the East button, but the dish is moving West. Go back to the rear of the ASC1 and swap around the black and red wire going to M1 and M2.
Once you have your dish where you want it physically on the East side...Go to your dish, pop the cover on your actuator and then set the hard limit(mechanical limit/hardware limit), with a screw driver.
Once that is done, come back into your house and go into the menu of the ASC1 and go down to resets and then position reset and hit OK 2 times.
Now your counter should read 0000. If not go through the reset again,or refer to the manual until it says 0000.
If you wish to set a soft or "software" East limit, at this point drive the dish about 10 ticks to the West, with the WEST button. Now go into the menu and set East limit.
Now you are ready to go back to your receiver and start setting up satellites.