I have a .pdf for the BHS28/40 and 52" fence and can email it if needed. They're all pretty much the same.
Here's how I tuned mine:
First, check and make sure your front guide tube has not shifted, the short section of the 'T' has the plastic glides and they're clean. If it's square to the top (ie: the gap between the rail and the top is the same on the left and right side of the top), get a 3/16" hex wrench and adjust the set screws on the short 'T' section of the fence 1/4 turn at a time, run one side out and the other side in until the fence is slightly sloping to the right of the blade as you're facing the front of the saw. Mine is adjusted ~.003" from the front of the blade to the back of the blade. Give everything a good coat of wax and you should be good to go.