Yes ! the BMW 700 recycles a number of elements of the 600, especially its chassis and engine.
but this car is a BMW 600 !
I leave you with the point !
You are right, that the BMW 700 recycled a lot of elements of the 600-type, like suspension, engine, gearbox, etc. But the BMW 600-bodywork sat on an independent tubular frame, the BMW 700 used integral bodywork with far longer wheelbase
Very interesting puzzle! Saw this car never before!