Cell phone. Don't leave home without it. :icon_smi:
I have a box of parts in my trunk with spares similar to what's in the first picture. I came across a new Fuel pump at a swap meet for about $5 so I threw that in there too.
I drove my e-bay 68 special from CA to Ohio with a handful of tools I carried on the plane. A few 3/8" drive sockets, ratchet wrench with short extension, phillips and straight screwdrivers, needle-nose and regular pliers and that was about it. Changed the T-stat outside Sacramento and the T-stat in NV along the way. (did not have a jack, front and rear bolt patterns were different so I only had a spare that fit the front, didn't have a lug wrench anyway but I bought a can of Fix-a-flat at Walmart somewhere in CA)