Is it possible to test these ideas without building a complete machine. Possibly. I have read many accounts of metal rings being made to levitate by connecting them directly to high voltage electricity, but as the rings are restrained by the length of the cables supplying the power, these experiments are usually not given much credibility.
It seems to me that these rings, when subjected to high voltage from an external source, are doing exactly what I predict the rotating rings would do, that is, surround themselves with a high voltage electric field, and also an open ended or distorted Dynamic Gravitational Field. This is indeed "anti-gravity", but not very useful.

A machine could be built relatively easily to test the rings that I propose. The ring would simply be held to a motor driven plate, preferably of insulating material, and then released at a suitable spin rate. A small diesel motor, or hydraulic motor with a vertical output shaft, would drive an adjacent vertical shaft by belt and pulley. The reason for the motor requirement is that the field which we are attempting to create, may damage or render inoperable, an electric motor, or a motor which relies on a spark ignition. A release mechanism could be made to free the ring from its attachment at say 100 RPM increments. The release system should have spring loading, that is it should be ejected, as the Fields may not form while attached  to the machine. Any testing of this machine should be as far away as possible from any electrical wiring, or apparatus. Way out in an open area. Safety precautions would need to be taken, as an out of balance ring could be dangerous. I would suggest a steel mesh enclosure to observe the experiment.
The ring should be of a magnetic nature, although the electrified ring levitation usually implies non magnetic copper. The reason for magnetic rings, or rings with magnets attached is that the complete machine that I propose MUST have magnets attached for levitation within a frame or housing.

Perhaps 2 aluminum sheet rings could be fabricated. Both about 300mm outside diameter and 200mm inside diameter, and turned down 5mm, and made to fit one inside the other. An array of (light) ferrite magnets glued inside, say about 30 x 22mm diameter, and the 2 sides riveted together. This should be tested incrementally for levitation from very low revs to the max of 450 meters/second at the outer edge. A number of variations could be tried including a second row of magnets, and perhaps varying the polarity of the arrays.

A successful result would see the ring rise from the base then fall to the ground. Increasing the spin rate would see the ring accelerating to a greater height. The ring would be expected  to fall as  air friction reduces the rotational speed.

It would be great news if this test provided a positive result, although failure would not indicate that the whole theory is invalid. It is probable that the generation of the required fields can only be achieved by insulating the rings from the ground.  This may require  building a complete double levitating ring machine, with the frame supported on insulating legs.

                                                    I have built and tested this machine.