Try this for size. Cook your meals before you leave couple days before. Once cooked and cooled down, put them into vacuum bags and seal close. Then freeze them. Anything else, if you can put into freezer, freeze it. Lot of water is good for this. Otherwise, everything else keep refrigerated. Keep food items as cold/frozen in a well insulated container. Keep soft and warm food in a soft insulated soft bag - toss in a frozen water to maintain heat gain in the sun. When cooking all you need to do is boil water in a pot (you can use a camp fire for this as well). It will heat your frozen dinners, you can use the hot water for camp showers as well as cleaning utensils afterwards. You can let it cool down and reheat for hot breakfasts (scrambled eggs, bacon, cheese). You can cook several items at once with the same hot water. Dinners can be served for singles or all at once (depending how you vacuum seal them). You can partial open the bag, serve yourself, then when the others are ready, they can watch the bag float in the water. You can heat with boiling water with an open bag, just have to watch it. Planning is a big thing when freezing meals. Basically all that is necessary is a properly size pot.
For the extend wheeling trips like you do that are continous on the trail, you should probably look into an expedition style trailer to match your Jeep. Lots out there in the expedition forums. Lots of knowledge and experience.
