For years I had a Pearl Beer metalclad cooler I'd set in the back. Like the one below. Had sandwich tray and everything. Never considered bolting it down, though. That's probably why somebody ran off with it. Today I have a Yeti cooler knock-off made by Lifetime Products. It will keep ice for several days and weighs slightly more than a cylinder head.
~ Jon 1952 1/2 ton with 1959 235 | T5 with 3.07 rear end