[joyridin']

I went out and looked at mine. I guess I never noticed it, but you are correct. My filler was added later. This might be due to my frame set-up. Where your tank is mounted, my tank could not be mounted in that area due to the frame support hoop that runs through there. This was probably added as the car was raced for about 15 years before being turned into a street car. Mine is an Arntz with a Butler interior. The gentleman I bought my car from was the original owner. He bought the car from Steve Arntz. It was bought partially assembled as a prototype Type 4.

Good luck with your Dad's car!