Spotted at 4:52 in this 1 of 5 Cobra video at Willow Springs.
https://www.youtube.com/watch?v=FTfjFSRExAc
Original Post
FWIW, out of only 37 factory built Gr-3s, Dale's in So-Cal and another in British Columbia, Canada are the only two known to be in North America to date. Since all Gr-3 parts were available from DeTomaso-Europe '71-'78, there are quite a few more undocumented Gr-3s that were home-assembled or done by Euro-based shops.
The Gr-3 Parts Catalogue (two versions from different years) is in the POCA Archives from Anders Hellberg's 'Gr-3 Registry' in Sweden. We also have a list of all 37 cars' serial numbers- from #1070 (pushbutton) to #8472 (late '78). There are also rumored to be two Stradales (unknown serials) built later that probably used leftover Gr-3 parts.