Max cool, blower low.
Do not trust auto-lo.
Since you are having problems.... you might need to borrow a good fan...
the air over the condensor is the bottleneck of all AC systems.....
If that is not sufficient it can screw up your diagnosing...
In fact i believe that is one of the situations where when using the sight glass to fill the refrigerant it can cause a false ' add ' signal... causing all sorts of other problems..
How about the fins INSIDE the evaporator being cleaned before you start any of this other stuff ?
This would be about the minimum...
http://www.northerntool.com/shop/tools/product_200007224_200007224