Yeah, I tried comparing the "flat" location to a picture on one of the parts supplier's web site. It gave a pretty good idea where the flats should point. One thing I found out the hard way is that the arm that attaches the asjuster rod to the back of the tensioner can be slipped on the tensioner flats backwards, resulting in very little adjustment range.

Also, I had a tensioner fail with no warning at all - except that it was 16 years old. Instantly stranded, with no makeshift way to go anywhere.

DG