disappointed that there was no wiring info
Wiring info is easy. Hopefully the original developer used the I/O addresses as the wire numbers (a lot of people do this). If not, the terminal block is labeled and you can easily add the wiring info yourself if you really want it. I never even bother with it.
Another tip: When working on a panel, take a high res digital picture or three, then you can have a virtual "look" at the panel if you're wondering something later at your desk. That would fix this problem for example. You could just correlate wire number to PLC terminal in your warm cozy office with the Scotch in the drawer.