There are a few things I'd add to your list, like

a fairly complete set of tools
engine oil
PS fluid
2-stroke oil
tarp
rags and gloves
LED trouble light
duct and electrical tape
fuses


And a few I don't carry, like

shovel
dog food

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Current Stable

• 380SL (diesel)
• Corvette C5
• Manx
• Baja Bug
• F350 Powerstroke
• Auburn Boattail Speedster replica