This is what the facility design wiring diagrams looked like:

https://imgur.com/a/niXkSt7

It shows that per-connector metadata that was added to each equipment symbol. The metadata allowed AutoLISP to do some really cool and intelligent things.

The PCB layout tool had interesting constraints. One of the issues was that pad graphics took up way too much memory. So, what I had to do, was to layout PCB's using a symbol that consisted of two lines forming an X instead of real pads. The symbol name encoded the diameter, hole size, etc.

When the layout was done, I had to unload a bunch of modules and then run an AutoLISP routine that would find and replace all "PAD_NNNN_X" symbols with real "PAD_NNNN" symbols before plotting.

Once ACAD migrated to Windows this was no longer an issue. Of course, by that time, accessible ECAD tools were around. I think my last ACAD schematic and layout was somewhere around 1993. I just didn't have the money to invest in ECAD tools of the era, so my ACAD tool served a purpose.