As John said, Hagerty's is superb, even for big trucks. They even will honor their breakdown-tow coverage for big trucks (on a flatbed carrier). Full-replacement coverage with full deductibles.

And, you can drive it for pleasure, etc, as long as it is not your daily driver to work, and as long as you are not using it to earn money. And, as John stated, you must store in it a locked garage and have other fully-insured regular vehicles (as daily drivers).

Tim