Well today I received Russ's 'camirror' tool and immediately decided I'll work it out.
Just last Friday, I made myself a new set of CBL's and STR for my Guardian. I made the CBL exact to specs, 38-1/4", and prestretched to 200# prior to serving the loop ends and closing the loops, then to 300# for the center serving. When I was done I was spot on at 38-1/4" end to end.
Today I checked the cam sync with Russ's tool and I was extremely satisified to see my cams were in perfect sync.
One thing I've learnt already...start checking the snyc on the 'top cam first'. Not a big deal...but I started aligning the tool at the bottom cam and when I moved it over to the top cam the 'pointer' fell exactly at my peep...not good. So now I align with the top cam first (away from the peep),then switch over to the bottom cam.
Of course after I was done I had to re-polish the tool, as it came spanking clean and after I was done with it my DNA was all over the tool.
Thanks a whole bunch Russ, this is one heckuva tool you've designed and built here!