RE: "Moisture eater" or silica gel -- location
Don't matter for the gel. Humidityor any gas/vapor doesn't concentrate in one area, it maintains constant pressure throughout the area. Put the gel anywhere and eventualy the whole cabinet will dry out. The heating rods area little different and should be placed near the bottom to encourage circulation. They don't absorb the humidity so much as warm things up enough to prevent condensation and keep any water in a gaseous state. Hope it helps.