Updated: Oct 7, 2022
As I learn my way into Commodore computers, I will post here any resources that I find helpful (recommendations from others, ones I find while searching online, etc.).
Schematics - /pub/cbm/schematics/computers/vic20/ (zimmers.net)
Schematics - /pub/cbm/schematics/computers/c64/ (zimmers.net)
Daniël Mantione's PLA20V8, the Commodore 64 PLA that you can build yourself