For non-stealth shows I always make sure to create some shade over the gear (someone mentioned an umbrella) and also bring some white hand towels to cover your gear - most decks and gear are black, which is not a good combo. For either stealth or non-stealth you may want to consider not stacking gear - I know my SBM-1 runs very hot on it's own, so I'd hate to stack a D8 on top of it in a really hot condition. I remember stealthing Dylan and Phil in the cow barn in Medford OR and jesus was it miserably hot in that big tin shed - I had my SBM and D8 right next to each other in a fanny pack like usual and the D8 went wacky and kept shutting off due to the heat (right in the middle of Positively 4th Street
) - in hindsight had I not had them right next to each other it wouldn't have happened, as the heat from the SBM pushed the D8 over the edge.
One thought for a stealth job would be to use something like a blue ice pack and triple ziplock it so there's no moisture and put that near the gear in a fanny pack to keep things cool...just a thought.