To help people who want to repair their vintage IBM EGA cards, I've put together this reference schematic and layout. The schematic is closely modeled after the schematic in the IBM technical reference material but with mistakes corrected and more information added. The PCB layout is closely matched to the original card. Using KiCad, you can click on a component on the schematic and it will automatically highlight it in the layout, so it's perfect if you need to probe pins with a scope, logic analyzer, or even just a multimeter.
You might be excited about fabricating this board so you can have your very own clone of the EGA card, but unless you have the full set of custom chips, the board will be useless.