Don't worry about it until after you kill one. The meat will be find in good game bags with good air circulation, it is actually better to let them air cool for a while before putting them on ice, a good thermal or breeze will cool the meat really well.
When you kill it, if you're solo and in the timber make a small meat pole in the shade with paracord, hang each quarter as you pull them so they can start cooling. I don't even bag mine until I have them hung, then I will trim and clean the quarters and put clean ready to cut meat in the gamebags while hanging. If your in open country just toss the meat ontop of a sage brush or any bush that will allow air to circulate.
Once you make it back to your SUV, drive to town and buy either a big cheap Igloo or a couple small ones, most towns have a place with dry ice, place dry ice along the bottom and put the meat in and close the coolers, don't put it over the top of the meat or it will freeze it solid. If you can't find dry ice just cover them with ice and make sure you're constantly draining the coolers.
Wind if your friend when cooling meat, if you're planning on driving home right after you kill it you probably don't even need ice. Once you're out on the interstate you can toss the meat on the roof and it will cool nicely at 75mph down the road as long as it's not sitting right on the painted roof, it needs full circulation, if you stop at night just hang it from the roof rack over the side of the vehicle. I've left sevearl animals hanging off my spare tire and roof racks in motel parking lots over the years. If you have multiple days to drive home I would definitely get it on ice after you're on the road but if you can drive through the night I'd just toss it on the roof and not be worried in the slightest.
