No, DF was a low power version ( and not very desireable) different heads, and cam, maybe pistions different not sure but it was most common early on in the early case.
DG was made early and late also.
the cast in head code is the real giveaway, also you can see the inlet posts where manufold fits are smaller on df to dg get a pic up of them with bits of rag removed for clarity and It will be clear, pic shows df gasket by dg head
everything else just bolts on so people could havd fitted a dg into a van that was origionally a df, heads could have been swapped too but lets assume not.
