My first ecomod was swapping out belt-driven fan for an electric fan in my Ranger. Not sure yet on the FE changes, but the engine (and thus cabin) heats up more quickly in the winter. Also, cab noise is noticeably lower.
How-to articles for the fan swap in a Ranger, presumably similar to the S10:
http://www.therangerstation.com/Maga...FanInstall.htm
http://www.rangerpowersports.com/tech/?p=126
My 16" Proform Electric Fan:
http://www.partsamerica.com/ProductD...egoryCode=6003