Vise Grips, large adjustable wrench, small adjustable wrench, Duct Tape, and roofing caulk that will dry in rain. God forbid you develop a leak in any part of the cooling system, those tools should enable you to access the leak and patch it long enough to get where you are going.
I also have a bit of a preference to a portable car charger/compressor with a built in flashlight. But they ain't tiny
