Thanks for the link, JLMoore3, it's a good idea, IMO, though I have a suggestion or two.
Before you start using these, contact cement a double layer of Lexan, Plexi, or plain Acrylic to the outer edges of the top, or you'll find the frame bending inward from the weight of the contents and the weight of the jug, things you put on top.
I know from 20 years experience with these just how badly they will bow in the top and a gallon of water or about seven pounds of weight to keep them stabilized, will be more than enough to wreck them.
A good piece of heavy plywood with Marine Spar Varnish, several coats all around, will substitute for Lexan, and, if you decide to set one unit on top of the other, make top plywood piece or Lexan one inch over sized on the back and sides, and use those outer edges to mark the outside edges of a five sided box, with the front open for trays/drawers
Buying and adjusting/hacking two more units will allow a more comprehensive chemical and rinse set-up for FB papers.
Pair this with a easily portable enlarger in a suit case, such as the Valloy II or Omega B66 and you've the ideal small darkroom for Travel Trailers/RVs, Corporation apartments, or Dorm rooms, without abundant running water.
Do no forget, old Samsonite hard sided luggage is your travel darkroom's enlarger's best friend.
IMO.