Hmmmmm....at first you said "C". The "A/B" is different from the a "C" as well. When it comes to the basic airframe of the F-15, all are the same. Key word "airframe".
There are a couple Strikes that when funds were allotted, those airframes were "D's". As a matter of fact, during the initial construction those airplanes were indeed "D's".
If you pull the CFT's off the Strike and fly it with -220 motors (Seymour Johnson jets) it will perform just like any other "tub". -229 airplanes (WA, MO, and LN) would perform better. However, the airframe is basically the same.
When I used order horizontal stabs, I had to be careful in which stab I ordered because when you take it out the crate, it could be light or dark gray. Rudders, flaps, ailerons, ramps, canopy's, and speed brakes had to go to the paint barn because those parts where all light gray.
Wings aren't made from scratch anymore. If a Strike needs a new wing, it comes from a jet in the bone yard.
Depot down in Warner Robbins has the ability to take a "D" front fuselage and graft it to the center of a "E". Same can be said with the other fuselage sections. The LN jet that cart wheeled when landing after coming from a Red Flag, although it's not flyable, has a "B" front fuselage attached to it and is being used as a weapons trainer at Sheppard.
So, besides a panel here and there, the basic airframe is the same shape and size. Yes different flight control computers, larger actuators, different cockpits, but airframe is the same :thumbup: