Truck and trailer side boxes

I've got one on the driver's side of my tractor, behind the fuel tank, looks like a large APU. Holds about 30-40 straps, plus a little extra space for refrigerating/freezing food in the winter.

There's also a 12" deep catwalk box between the rails with the door facing up, contains my most seldom-used tools, but that one doesn't have a latch and requires a padlock or some such thing to keep it closed since the door is 'spring loaded' to stay open about an inch. The padlock that's on there rusted up after a few months and I'll have to use the lock cutter to get it off when I decide to open it, and then I'll have to wonder what to replace the padlock with. Maybe one of those steel bolt cargo seals.