Quite a few of your questions might be answered by looking over the CT Gallery.

However, I'll take a stab.

#1. Can't help you on the "CT110A", "AC" & "AW". My Zedder Honda Cross Reference Parts Database shows CT90's and CT110's with the letters "A", "B", "C", etc. but not the "AC" or "AW".

#2. For Australian parts of the 12 volt "Postie" version, the best source of information can be found at some (but not all) of the local Australian Honda dealers. Another place to look is at CMSNL in the Netherlands, as under the CT110 on-line parts database they do list several years of the Australian Postal Ministry CT110's. The 12 volt Postie version of the CT is a purpose designed motorcycle that has been used by the Australian and New Zealand postal services and thus can be hard to find details on. 

#3. The U.S. 1980 CT110 frame part number is 50100-459-670ZA
The U.S. 1981 CT110 frame part number is 50100-459-770ZA
The U.S. 1982 CT110 frame has two part numbers is 50100-459-770ZB and 50100-459-770ZC
The U.S. 1983 CT110 frame has part number is 50100-459-780ZB
The U.S. 1984 CT110 frame has two part numbers is 50100-459-780ZB
The U.S. 1986 CT110 frame has two part numbers is 50100-459-710ZA and 50100-459-900ZC

Pretty much all the same with very minor differences. Why do you want to know this information?
Changing frames with a stamped in the frame identification number when you have a title can cause some extra steps with the motor vehicle registration, but, other than that, it should be OK to do.

#4. The Large Rear Cargo Racks that have a "stock from the factory" bar on them are from CT90's, 1969 to 1979 and the bar should always be towards the back. The Large Rear Cargo Racks without the bar are "stock from the factory" on CT110's.

#5. See answer #2 above.


Paved roads, just more needless government spending...

I pick up my mail in Santa Barbara, California, USA.