What about a marine spotlight? They even have remote controlled ones that you could mount on your truck and tilt up to check the fuse while you keep your curls dry inside your truck cab. A lot of marine power systems are 12v.
Another option, if you want a flashlight, would be the ones the navy/coast guard use. My brother is a CG officer and has a discarded military flashlight. While the battery was good, it threw a highly-focused beam that was still tight a 1/4 mile away. The base is a 7"W x 5"D block (OK, OK - 18cm x 12 cm), top carry handle, rubberized weather-proof, that sort of thing. I'd imagine they were used for spotting shore stuff from a boat 1/4 mile out through fog. Maybe you can find a NZ navy or cg station that could help you out.
Just a coupla ideas.
