We drove back with ours two years ago. We had foam 6 coolers roughly 36 x 14 x 14. not sure what the shipping boxes look like but I think these were the same coolers they use for shipping minus the outside cover. When you heading up?
Laylow, yes my brother and I each killed a small bull a couple years apart in Maine. The 1st year we filled 2 100 qt. and 1 110 qt. coolers completely full. When I shot mine we had taken a 4th cooler incase I got a bigger moose, went to pick up the meat and it all fit in just 2 coolers! Moose were similar in body size.
I had 6 of the boxes below. Approximately 300 lbs of boneless meat. I didn't ship it, but hauled it in my Chevy Suburban in the boxes. The meat was boned out, vac sealed, and frozen. We put the meat into plastic bags (like a garbage bag), then the styrofoam box, then the waxy cardboard box. The meat was still frozen solid after 40+ hours of driving and/or sailing on the ferry.