Waterproof ATV Storage Box

I wanted a better storage box for my Yamaha Rhino side by side.
I wanted it to be better organized, with compartments for different size ratcheting straps, chains etc...
So I threw this box together, built with 3/4" 'good-one-side' plywood.
All the seams are glued with LePages wood glue, 2" brad nails and then reinforced with 2-1/2" #8 Robertson wood screws, so it's very strong. As well I reinforced the lid of the box with metal diagonal brackets and the box itself with angled strips of wood glued into the corners.
After building the box I wanted some way to 'waterproof' it and decided to try applying engine oil to it, the idea being that the oil will preserve the wood and help it repel/shed water.
Kinda not really sure how well it will work. Experimenting here a bit actually...