That gadget helped a lot. The problem is that you can’t get enough leverage on the little knobs to get a feel for how far you’ve tightened them. (Tightening lowers the bed, and loosening raises it.) If the nuts are too loose the opening scrapes the bold threads and hangs up the bed, which creates a false reading. I actually unscrewed the rear bed knob completely trying to raise the bed because I didn’t understand that you have to start with the right tension.
Understanding this, the bed was out of alignment quite a bit and I didn’t have any way to tell because I thought the nuts had been over-tightened when they hadn’t. Very enlightening process!