Johnny, to be honest, all F-15's weather the same and it really depends on how dirty you want it. Since the 48th FIS was stationed at Langley, all the F-15's would have been spotless. Since it's the [former] home of TAC, it's the same base that had airman painting the grass green (I kid you not).

From personal experience, you would see some grease stains from the actuator locations, and a little bit of panel chafing on top of the wings and the engine humps. There will also be chafing from the aft end of all the gear doors, and black coking from the JFS exhaust.

I'll see what photos I can come up with of my jet, and others from my last squadron. Ours were kept pretty clean too, but still show all of the above wear & tear.