Someday, I'd like to have another one.
I had three GTs when younger- I brought two of the three back from the dead. LIke most Opels in the USA, they were vastly misunderstood by most owners- but I could make them run like they should, consistently. I think I still could rebuild one of those 35mm single-barrel Solex carbs (1100) or one of those 32/36mm two-barrel Solex carbs (1900), even now, with a little time...
The one in the picture above is a bit of a head-scratcher, though. It's got the US badging on the side but the European-style clear-lens parking lights above the bumper (those were amber on US models). I know it's pre-1972 (the non-opening rear quarter windows give that away), but without the original wheels, or being able to see the interior (the idiot lights in the dash were rectangular in early models, but round in later ones, and the drivers door window crank went from low on the door to high on the door in later models too), it's hard to pin it down more than that...
Regards,
Gordon.