Help with a VPI 3D Tonearm Exchange

Undertaking to trade out my 10.5i and Classic arms with a pair of VPI 3D arms and I am hung on a mechanical question. With the 3D Arms came a pair of replacement pivot points that are made of two machined pieces, essentially a screw and a nut. The screw piece, on its top, has the well and spike in the center that serves as the tonearm pivot point.

The existing pivot installed in the tonearm platform appears to be releasable with the unscrewing of one of the small screwlets that VPI uses in their tonearm assemblies for various adjustable pieces. In this instance though, when I remove this screwlet, the tonearm pivot doesn't slip out of its hole in the tonearm platform. Nor does it appear to unscrew into a nut and screw assembly.

Any ideas on how to get the existing pivot point out? I don't want to force anything for fear of breaking something or damaging the finish.

I purchased the arms direct from VPI so I don't have the benefit of a dealer to help and there are no instructions in the box. A call on Tuesday to VPI will get me some help but if someone has a thought I might not be hung up till then. Thanks.
I assume you are referring to the pivot point bearing assembly. On the older bases, the pivot bearing was dropped into a hole in the dog leg platform and then secured in place with an allen head grub screw. To take the older bearing out, simply unscrew the grub screw, and lift the bearing upwards out of the placement hole. If the bearing does not come out, take the vta base off the table and gentle tap the bottom of the bearing until it releases.

The new bearing is a drop in replacement with the exception that it has a threaded bottom which allows the bearing to be tightened to the dog leg support thereby providing better mechanical coupling.
Yes...the 3D arms have a different base....I got the arms with base, so just screwed it into the top of my perfectly. By the way...I prefer the Discovery to the Nordost...
will a classic 3 arm fit on the 3d pivot point, or do I need to change pivot points every time I swap cartridges(arm tubes)?