I've boned them out and left the bone in, but if I leave the bones in I always slice vertically down the hindquarter along the bone then fillet the meat away. The bone is still attached but this opens the surface area to allow the meat on those thick hindquarters to cool quicker. I either hang the bags from a tree branch or make a meat pole so the airflow helps to cool the meat. If you can hang the bags by a creek that is even better. Living by the coast we get flake ice from fish processors and have a couple coolers filled. Once the meat is back at the truck it goes on a bed of ice and then is layered over. I've kept meat 5 days on ice like this before getting home to process and never had an issue. Tons of variables but this has worked well for me.