Oh? Sorry, didn't bother going back to that thread after the trolling started.
100 extra horsepower, give or take (as compared with early E-7s and FTH horsepower), slightly less drag (pointed spinner), early models based off 109E-4/N later models E-7/Z with even more boost at altitude, possible use of 90-round drums on the MF/FF (still hard to find details about this later ammo drum, even Tony Williams couldn't help on the matter of when it was used and where). And, of course, plumbing for the centerlne drop tank to nearly double fuel capacity.
EDIT: As you mention the major parts of the airframe were the same -- but the same is true of 109Es to 109Ks... Essentially the same frame. The total package is different though.
P.S. Outside the "same old BS" that was not a luftwhine. A description of why the overboosted spitvc was not good for AH. Also note the 109F lost use of its gondolas and its bomb (I agree with the gondolas on historic principle but not necessarily the bomb).