There's a few good locations around SDF
to catch some of the UPS heavies - mainly on the west side of the field like the nevada ave. location on bruce's site. there is also a location further south along that perimeter road (it looks like a construction entrance). it is right across the runway from the 747 ramp. there is a tall fence there however....but it allows you to capture stuff taking off that you would only see turning onto the runway if you were at the nevada ave. location (although that would be nice for the inbound ups push). i'm sorry i can't give better directions than that, but i think you'll see that it is relatively easy to find. i would watch flightaware and take note of the time of the inbound/outbound UPS pushes so that you can find the best time to go.
With Lexington, there is always the Kentucky Museum of Aviation which is one of the smaller museums around but definitely worth a visit. The folks there are very nice and are more than willing to help you out. One of their newer arrivals is an F-14 from VF
-32 Swordsmen, although it is sad to see its engines and such gutted.
hope this helps...and enjoy your vacation!