Optisan EVX 4-24x56 Parallax Wheel

I ordered an Optisan EVX 4-24x56 with the factory side wheel from Jeff earlier this summer. I talked to him before placing the order and he said that there were some complaints about the design of the attachment between the paralax knob and the fac wheel. When mine arrived I soon saw what he meant. The paralax knob is tapered as is the mating ID surface of the wheel. Tightening the set screws seemed to force the wheel away from the scope. In short there is seemingly no way to maintain a positive attachment. The scope itself is great (very clear with a good reticle). I returned the scope to Trenier (thanks Jeff) because I wanted to use it for FT but the poor side wheel design would make that impossible. Uj