I have stumbled onto the SOLUTION for the JVC projectors giving off HORIZONTALLY polarised light!!!
If anyone read some of the testing posts I made, I found that the horizontal polarisation of the JVC units meant that standard RealD glasses would not function in an optimal manner.
You see, all circular polarisers have a layer that is actually a linear polariser built in. And, for the best extinction ratios, the linear component in the glasses must be 90 degrees offset from the linear component in the projector lenses.
In the case of our system here, RealD glasses' linear component are Horizonal, and my projectors are ALSO horizontal, meaning that to get the best extinction, I either had to hold the RealD glasses sideways, or hold the projector sideways (chuckle), neither of which was what I wanted. (RealD projectors in the theater are vertically polarised before the circular polarisation is applied).
SOoooooo - the Solution???
It turned out to be very simple, and the light bulb went off after I did some more reading about the physics of the optics involved.
You see, if you combine two quarter wave plates (the film used to make the circular filters), you can create a half wave plate, which is COMMONLY USED to change the orientation of polarisation in lasers and projectors!!
That means I can EASILY convert the HORIZONTAL polarisation of the JVC projectors into VERTICAL!!!
MAN am I happy right now!!! I will be able to use my stock of RealD glasses after all, and no custom work will be necessary.