The original DOD units had "balanced" XLR output as well as the normal 1/4" jack and no footswitch. This has been adapted for stompbox use and could work well with acoustic guitar.
This is a library of perfboard and single-sided PCB effect layouts for guitar and bass. I'm not an electrical engineer by any stretch of the imagination, just a DIY'er who likes drawing layouts. It is meant for the hobbyist (so commercial use of any of these layout is not allowed without permission) and as a way to give back to the online DIY community.