I think it's intended to be an MG-42, but ultimately I think Indy takes place prior to '42 making the gun (if that's what is in the movie) inaccurate... Instead they should have MG34's mounted on them, but either way I'll 100% be removing that monstrosity off the back...
For anyone curious, Target has $5 Germans out right now that several come with an MG-42... It would be simple mounting one to the back of the German car I think.
I hope we get a cool German w/bike & sidecar too for this chase set as well at some point. Seems obvious, but you never know. The bike's a little on the "chunky" side, but it's pretty outstanding looking still, and I can just see it in desert tan with a guy in the sidecar and a guy on the bike, and some goggles.
And I agree with speedermike, we need a German with goggles, period, for these. If you want, again, 21st's line at Wal-Mart has some DAK Germans, as does Toys R Us, and I believe there's one figure with a headsculpt that has goggles down on it that would work perfectly.