I plan on painting my 4Runner with tractor paint sometime this winter. I plan on spraying mine rather than rolling it on. If you have the tools to spray it (compressor, gun), I'd suggest going that direction. Rolling it seems like it's labor intensive.
Here's a thread with some pics of a truck that was sprayed with orange tractor paint. Turned out nice! That's the exact color I'm looking to plan my rig.
http://board.marlincrawler.com/index.php?topic=64172.0