A and A+ (later referred to as the B) could be recognized by the burner cans and some subtle RWR antenna differences. The D had the burner cans of the B (GE110-429 motors!) but all the avionics were different. New radar (basically an F-15E radar with more power and a bigger antenna), MFDs, a real HUD, Link-16, ASPJ (antennas in place of the leading edge extensions), and a long range IRST (hence the double chin pod). Ejection seats were the NACES as well and look different. No loops on top of the seat. There is also a box that sticks up in front of the back seat. It was for slaving the Radar, TCS and IRST to each other in creative ways.
