I don't have a solid reference for it but I know a few differences for sure... First of all wich E's and F's are we talking about? From the externals F's and later E's are pretty similar. Early E's had the different gun nozzle for example.
These are the differences I know without looking them up, But I can try to find some sources.
Later E's have the sloted stabilizer, F's don't have this feature
F's always had the agile eagle upgrade (slats)
F's where initally unable to do aerial refueling (It was removed once they where in germany), but the AAR capability was restored in the Peace Rhine (?) Upgrade (this one also gave them Mavs and the AIM-9L and so on.
F's never carried Sparrows, they were Sidewinder only until early 90's with the KWS/ICE Upgrade (the launchers/ejectors were'nt installed and the APQ-120 wasn't able to support AIM-7's)
F's lacked the aft most fuselage tank (Nr. 7 ircc)
F's never hat the TISEO
F's and Late E's had different formation lights than early E's, they're a bit wider.
And then for the armament, the initally F lacked most of the guided/smart a/g weapons and sensors (no Mav, no TGP, etc.) it was pretty much only capable of dropping dumb irons and fire rockets