Hi Don, I didn't even give the fuel tanks a thought, I reline or replace my old tanks after storage anyway but when I do the rebuild on them I usually have to flush out that nasty old oil that gunks up. Don and I both live in pretty dry climates so we don't have a lot of storage trouble. I leave my fuel in my shop without trouble, I have even used up my old K&B fuel and it was just fine, that was some old fuel!!! What we don't have is high humidity so we aren't bothered with moisture. My shop goes from 120 down to the mid 20s, {But it is a dry Hot and Cold!!}
When I put a plane back together I also clean all my wires with electrical cleaner, the RX too but as Don mentioned, I don't live by any body of water at all.
You may want to follow Camps instructions living in your area of the country.
But it's a dry Heat!!! So is Fire!!!