Help with counterweight on VPI JMW 3d tonearm


I recently purchased a package on Audiogon that contained a VPI Classic 3 with the JMW 3D tonearm. The tonearm has a counterweight on it with the Soundsmith Counter Intuitive applied, but it is firmly attached to the arm and it has no set screw along the perimeter to loosen. The only hole in the counterweight at all is on the body of the weight in the back, but this hole doesn’t take a hex wrench and appears just to be threaded. I wondered if the previous owner had covered the set screw with the counter intuitive sticker but Ive felt the entire perimeter of the weight and feel nothing that I could use to loosen it. Can anyone help me identify this weight and suggest how I might loosen it? I’ve reached out to the seller but so far I’ve gotten no reply and I’m frustrated, can’t set up the tonearm/cartridge obviously. Dropbox link below contains a picture of the weight

https://www.dropbox.com/s/0nn05bhdmaur7u5/IMG_6397.JPG?dl=0
davelarz
Dave - the early 3D's worked with friction (as you found out)....the newer ones have the set screw again.  Harry told me to use some light oil, but I didn't tell you that because sometimes its very difficult to take the sheen of oil off the arm.
Well there you have it - I got it loosened. Having never seen one of these teardrop counterweights without a screw I was sure it was screwed on there somehow and so I didn't want to apply too much pressure to move it and scratch the arm. But I just worked it a little bit and it moved.

No set screw in the counterweight. Huh. It's always something
It might be under the counterintuitive.  BTW, my early JMW-12 doesn't have a set screw.  
But doesn’t every vpi counterweight have a set screw at the top of the weight, on the perimeter, that screws into the tonearm? Because this counterweight does not have that screw. My classic 1 JMW arm had such a weight - you loosen the screw at the top with the appropriate hex wrench and then you can move the counterweight. Every picture of every vpi counterweight I can find has this screw - in the absence of it I really don’t understand how one is to loosen or tighten the weight onto the arm. Are you telling me you have experiences of vpi counterweights that have no screw at all, that you don’t tighten or loosen anything you just move it back and forth and leave it there? I’ve never seen this. 
Agree with @stringreen and add that you might want to try a drop or two of a light oil and allow time for the oil to penetrate into the joint.  It might also be that the joint has seized over time and needs a little extra umph to break it loose.  But, as stringreen indicates, go slow.
Dave - the weight on all VPI 3D arms move along the back end of the arm tube.  It is very hard to adjust properly on these older arms, so VPI then included the Counterintuitive to make it easier.  I would try to rotate the counterweight without the counterintuitive in place (just slide it off the weight) while pushing the weight itself either forward or back toward your needed VTF of the cartridge. (clearly there is too much friction) When you get it in the approximate place, then use the counterintuitive to slightly add or remove weight to get to your needed force.  I know it is difficult and inconvenient to move.....the very early 3D's didn't even have the luxury of the counterintuitive.  Go slow but be assertive.  The new 3D's are much more user friendly. Good luck.  Let me know how it goes.