I emailed RVREVO one of our older members and a good friend who has been away for some time. He is well and sent me an email on the Golden Jacks.
Golden Jacks.
All the wheels are different.
Mini Marcos is the Smallest.
Corvette is the Widest.
Rolls-Royce is the Largest.
Camaro, Toronado and Hillman Hunter are same size.
Camaro and Toronado are same wheels.
Forgot to add the Rover.
Further to that are the sizes that Corky already provided
Ok, Camaro, Hunter, Toronado, Rover and Corvette are 15mm
Marcos is 12mm
Rolls-Royce is 17mm