First spy shots of the Volt-based Opel Flextreme?

We've already seen the first evidence that the 2010 Chevrolet Volt has made the jump from the computer screen to the real world, and it looks as though the Volt's European cousin is following the same progression. Spy photographers have spotted what appears to be the first mule for the Opel Flextreme.

General Motors first showed its Opel Flextreme concept at the 2007 Frankfurt Auto Show. The production Flextreme will ride on the same E-Flex platform as the Chevy Volt, although GM will likely replace the Volt's gasoline engine with a diesel unit.

It's no secret that engineers from the General's Opel division have been working on the development of the upcoming Volt and, according to The Green Car Congress, Rick Wagoner has publicly mentioned that a second E-Flex vehicle is currently being developed along side the Chevrolet in Michigan -- one for the European market (as in Opel).

We're not going to speculate as to exactly what is being tested in this E-Flex mule - - only that it is an early developmental test mule for the Volt and it's overseas cousin.