The more I learn about the ACI the more I'm leaning toward not messing with it. The ACI requires -16v unregulated power and a fair amount of additional components to get it to work with Vince's kit. Bottom line, it was designed to work with the original Apple 1. There are plenty of sources for full size Apple 1 replica boards, and a source for Vince Briel's Replica 1 with the expansion slot. America is a wonderful place and you can pick what Apple 1 you want. I'm going to continue on my original path and focus on the keyboard and case. After my kit is ready I'll publish the KiCAD files on Github and y'all can have a crack at adding the expansion slot.