I don't think there are any smaller versions of the doghouse proper. There isn't a vast amount of excess clearance between it and the engine and transmission to possibly eliminate.
The clip-on front sections are interchangeable among many model years (and pretty much any variety of E series van or chassis), and there have been a few variations in the shape and configuration of them. There are probably a few aftermarket versions available as well, I suspect. If you do some searching online (or at a decently well-stocked junkyard), you might find one that works better for you than whatever version you have. If worse comes to worse, you can of course remove the clip-on part entirely and the vehicle is still perfectly safe to drive, though less convenient for storing odds and ends and holding cups.
