| Hi again Harv,
Getting back to your questions, I have measured the various bungs accurately using the plastic ruler that came with my wax crayon colouring set, and they are exactly as follows (ish):
Front right - depth 25mm - diameter 35mm
Front left - depth 30mm - diameter 20mm (skinnier)
Rear right - depth 40mm - diameter 35mm
Rear left - Doh!
As I said before, the rear one is well proud of the wheel rim and will protect the wheel.
Spinoli | 
Threaded Mode