Plastic Axle!
I made an Axle from plastic tubing. One long tube that goes through the Gyro Box and two larger - shorter ones, one on each side.
I cut the end off two Ball Point Pens to make two larger Axle Sections that fit over the first two. The fit right in the centers of the Indy Vette Wheels.
Here are the Wheels glued to the Axle.
More Coming...