Use them. If necessary, cut out fronts with a circular saw. I use 12x12x4" deep plastic parts bins that were freebies, set at 24" ht. They can be pulled and stacked for taking outside to hose off, but I never have had to do that yet. Seems the chooks do not poop in them or sleep in them either. Plenty of roost space up at 48" height on opposite wall. I have dividers between nests, but no tops over them. That way, I do not need to leave lights on in coop as enough light will be present. I just keep them filled with grass clippings.
I have 24 pullets and 10 nest boxes at 24" ht. Those crazy chooks all try to use one nest on the far left. They will even wait and squawk for another to finish. It is nothing to find 5 eggs in the one and a hen readying herself to lay yet another ! Still, mine are very young, just 5 1/2 months and averaging 6 to 7 eggs daily. They started laying at 4 months.