I thought I'd posted this here back when I installed this, but apparently I forgot.
Craftsman tool box, $5 at the flea market. Its big enough for the quart of oil & couple of ratchet straps I needed a place for. I drilled holes & installed nutserts from the bottom of the bed, with wing bolts through the bottom of the box, so it stays in place, but can be removed if I am filling the bed with dirt or gravel.