Unfortunately we still don't know what platter you are talking about from the Aries. Is it black, just like the MK III platter? What does the bearing look like on it? Does that bearing measure the same as the MK III bearing?
I'm asking this because VPI changed the bearing from the old, original MK IV bearing, going to a nut type configuration and I believe the diameter changed on it at that point, so you would have to drill the plinth to make it fit. They also changed to an inverted bearing type at another point, which also has a different sizing I believe.
The best bet is to wait until VPI gets back from holiday, or just look at both bearings and take measurements, if you can.
Good luck