Care and feeding of true barn-find systems

[Alan Perry]

Yesterday I rescued a Sun 3/260 that had been sitting in an open barn 
for years. It had been "running when parked" a dozen years ago.  It 
seems to have been covered by a tarp, but otherwise unprotected. All 
things considered, it doesn't look that bad but it is pretty rough.

Any pointers on things that I should and shouldn't do as I start trying 
to bring it back to life?

alan