If anybody decided to spend lots of time thinking about how I do things, they might comment that I sure do seem to use hose clamps as much as I possibly can.
Above are feed and water bowls fastened with those really long hose clamps. They work quite, though not fantastically well. The army surplus bowls taper slightly which lets them nestle into each other, but makes any fastening a little bit complicated. The most important thing, however, is to avoid the bowls tipping away from the dog and spilling everything outside, which the they rather object to.
Water can be filled from the outside. I've tried feeding from the outside too, but that just turns into a mess except when bones are on the menu. The time you spend opening and closing doors and gates adds up if you have a large team, but now that I've cut down I might as well spend some quality time with the mutts during mealtime.
Modelling this system is Bembo, taking the opportunity to get a nice nap.