GRD F3 in Germany

[jkeller]

I am trying to find information about a GRD F3 car that belonged to a man from Germany named Peter Weber.
Mr. Weber had two cars, one that was Tony Rouff's car from 1973 and 1974, this one then went to Dan Greer (an American in Germany) and then to Peter Weber.
The other car is a mystery.
Dan Greer entered several German F3 races under the banner of "Challengers Racing Team".
At the same time, there was another driver, John Rust, that was entered as Challengers Racing team as well so one would assume they were team mates.
Does anyone know of Dan Greer, John Rust or Peter Weber?

Thanks,

Jim Keller

[Scala]

Would it be something like Mike Snowdon's car, run in Formule Libre at Mosport last fall?

http://74.103.2.134/track_gallery/CA.../IMG_7801.html

[jkeller]

My cars are very much like Mike Snowdon's car. His GRD is a model 272, a 1972 Formula Atlantic / F2 car,
mine are 373's, 1973 Formula 3's
Basically the chassis are the same and the cars look very similar except that the F3's have smaller wheels and tires and, I think, smaller wings. Engines and gearboxes are also different.

Jim Keller