I agree, I wouldn't block it off. It helps remove built up engine heat from your engine bay. An engine is nothing more than an oven, leave the over door open. A 5minute engine clean every week or so is a lot better than a having to replace parts from heat build up pressure or what not. It's there for a reason. And I'm like you, my truck is detailed often. If I were in your shoes I'd be looking at doing it properly. If you are THAT concerned, maybe look at some kind of hydraulic release mechanism that you can open and close from inside the truck. When you want cool road air, push a button to open it. Butttttttt, that still sounds like a shit load of work for very little reward, if anything, just plenty of hassle. My truck is the blackest thing on this board, engine bay included and even I have no real issues. Nothing a good spray and wipe doesn't take care of. 2c