Abbotwares purchased their chassis from an outside supplier - most likely Emerson. I would simply look for any given radio with the same tube count/type as you have now, and follow that - with a grain of salt or two.
Keep in mind that after your 5th or 6th AA4/5 radio there is not much left to learn and basic repairs become automatic. At this point, I can take about any AA5 radio that has not been mechanically trashed and bring it back to life, and do an adequate alignment (without instruments) in under an hour. Yes, I will use an SG and VOM to do the final tweaking, but most of the time, surprisingly little additional adjustment is needed.
And, you could always draw out the schematic and then compare that back to what you find on-line, if you are really curious.
Peter Wieck
Melrose Park, PA