That's because the D7F engine has an eDIS module..
You need to get the rev counter converted.. cost me £75 like, 2/3 years ago! (And then you get a new wire on the back of the original dials, and connect it to one of the outputs on the eDIS.)
Or, find some 1.2RN Mk1 Phase3 dials.. and see if they work.. as that was the D7F and had a rev counter.. *may* work, dunno.