I am curious, are the engine block and cylinder head the same on the 2007 carbed and 2008 injected engines? Could you take an engine out of a 2007 bike and put it into a 2008 bike and hook up the throttle bodies?
Engine's differ , in the following :- 1:- engine capacity , carb =790cc EFI = 865 cc 2:- the cam's are different profile , not sure on how. 3:- crank position sensor ? Not too sure but I'd think so. You'd need to compare the sensor part numbers , if they are same it will swap over , but because cam profiles are different , the fueling would be wrong either way round you are going , you might be able to put the 790 cam in if going for carburettors with 865 cc ?
Converting an EFI bike back to carbs is, usually, somewhat easier than the other way round. I helped a mate do it years ago on one of the first, injected GPZ1100's. When the carbs are mounted all you have to do is jet to suit. Modern EFI systems are more reliable but way more complex with numerous sensors and additional wiring etc, then there's the mapping.