Oh goodness, this is the kind of thing I've been trying to find for years now: some method of making a computer from scratch, as in from raw materials.
The Great Tinkertoy Computer [1] is made from raw materials, although its specific rather than a general purpose computer, and had computer aided design although back in the day it was via a PDP-10.
[1] https://www.computerhistory.org/collections/catalog/X39.81