Just for the sake of closure on this topic--
The a/c is still broken...
...and I guess that the lack of plywood to crawl on is an issue for more then just me because the gas company (she apparently has a repair contract w/ them for the heat and her separate a/c system) would not go up there w/o a sub-floor, they said it's an OSHA regulation that they are not permitted to move around in attics that are rafters only.
We called another company that my dad used for his heat pump a while back and they seem to not care--they will be here this week hopefully and I will post some closure to the AC problem.
I did as much troubleshoot as I could--
* fuses for air handler and outdoor unit are verified good, and AC detector lit up when put near the romex in the attic
* re-made all the thermostat/control wire interconnects in the attic using beanies--they were previously just twists and covered in duct tape
* verified that jumping G-R or Y-R at the thermostat do not activate either unit
The thermostat has typical 3-conductor setup--G (blower?), Y (compressor?), R (voltage?)
The air handler has 2-conductors
The compressor has 3-conductors
I was unable to locate any low-voltage AC between any two wires of the 3-4 connections in the thermostat bundle up in the attic, so I assume that means the transformer is kaput or the wiring is damaged elsewhere (probably outside unit due to animals or nature)
Since the air handler only has 2 conductors going to it, and the compressor has 3, I assume the compressor is where the transformer is.
My dates for the system are off by 10 years--it was installed in 1969... but it's 100% original
... outdoor unit, air handler, etc... the only piece that has been replaced, and I mean ONLY piece, is the outside power cut off which was replaced ~10 years ago.
It's a Carrier system, the outdoor unit is labeled as model: 38GF004320
If I ever am in the market, they're the guys I'm going with.
Come this fall a buddy and I will be laying plywood up there to help with future service.