Joyridin - We're over the moon with the quality of the car. I need to head over to Dad's place and get another set of keys cut. You never know when I might get to take it out for a sneaky blast over the nearby mountains while Dad's out of the house...!
From all of the images that I've seen of virgin unbuilt Arntz cars, there was no provision built into the body for a filler cap. From what I've been told and seen, most factory built cars had the filler cap located where Dad's sits - as per 289 Street Cobras...
Many home built Arntz didn't have an external filler cap fitted, and it seems that guys are fitting a 427 style filler cap in the rear quarter in subsequent rebuilds. I think what Dad and I like so much about this one is that it has lots of the signature pieces that make it instantly recognisable as an Arntz.
Here's a factory Arntz brochure from 1978. You'll see from the aerial photo that the factory demonstrator had the notched hood, forward braced roll bar and no external filler cap.
Dad, this brochure mentions
"inlayed frame rails (optional) that contribute to solid front-to-back body rigidity" That explains the extra frame rails that we were looking at inside the sill panels...
Lobelly - yep the light is what makes the difference