Really nice looking set. AK built them like tanks, which is why they went out during the depression. Old Mr. Atwater didn't want to compromise on the quality so he just closed the doors.
Since you have the chassis out, look underneath and see if there are any modern capacitors under there. If it has been recapped, it should be good to go. If it has ancient looking caps, you should recap it before using it.
Schematic and parts list:
http://www.nostalgiaair.org/Resources/042/T0000042.htm
See "Chassis H-1"
Identify your cabinet and model by matching photos:
http://radioatticarchives.com/
The Nostalgia Air schematic is from a Model 72, so you might start with that. I have a 55 and a 60-C in a Kiel table. The 60 has all its original balloon Cunninghams including the 45s.
[Edit] Here's one more good reference site for AK information:
http://www.atwaterkentradio.com/
You might want to post in Barter Town or the classifieds for an 80, maybe someone would send you a used one for 10 bucks.