If you do the gutless correctly, no ground tarp needed. The carcass/torso is your table. Get the hide down past mid body, and as you pull quarters off, just lay them on the cavity that should be clean, and into the bags. 
For the elk hunters amongst us, gutless anything smaller than an elk, a deer or antelope for example, is about a 25 minute task. Feels like you're breaking down a squirrel.
I'd defiantly get the hide off of the quarters. I've never done that, but in my brain, it just goes against everything there is to cooling down your meat. If I decide to debone, I either do it right on the table (the torso) or I always carry a contractor bag, and will do it on that.