Sdcampbell -
If it's like my JMW 10 - and it looks like it is in photos - there should be a set screw on the left side, just below the height adjust knob. You can adjust the arm to spindle distance by rotating the arm base. I used the JMW jig and snugged the base into the jigs "vee". Measuring the pivot to spindle distance by ruler with the arm removed showed it to be spot on - 250 in my case. It had been maybe one or two mm long. That was enough to create sibilance and mistracking problems that drove me nuts for a year. I attacked the problem from every parameter and learned a lot in that year. Setting the digital scale to the side of the platter and taking the reading at the same height as the record surface is critical. I wonder if that is a unipivot thing. The Fozgometer is a fantastic tool. It got me in the ballpark but the best azimuth setting was found only by slight tweaking after the initially setting for balanced output. The difference was big in my case. YMMV
If it's like my JMW 10 - and it looks like it is in photos - there should be a set screw on the left side, just below the height adjust knob. You can adjust the arm to spindle distance by rotating the arm base. I used the JMW jig and snugged the base into the jigs "vee". Measuring the pivot to spindle distance by ruler with the arm removed showed it to be spot on - 250 in my case. It had been maybe one or two mm long. That was enough to create sibilance and mistracking problems that drove me nuts for a year. I attacked the problem from every parameter and learned a lot in that year. Setting the digital scale to the side of the platter and taking the reading at the same height as the record surface is critical. I wonder if that is a unipivot thing. The Fozgometer is a fantastic tool. It got me in the ballpark but the best azimuth setting was found only by slight tweaking after the initially setting for balanced output. The difference was big in my case. YMMV