[Hallicrafters] SX-28 questions

[K9MUF at aol.com]

Fellow Hallicrafter fans,

I am trying to resurrect an SX-28. In the process of recapping it, I noticed 
that there are wiring differences in it and the schematic in the manual that 
came with it.These variations seem to be mainly in the AVC and ANL areas. The 
wiring seems to be original factory.
Does anybody know of any version changes that could account for this. The 
receiver serial number is 118973 and the date in the manual is Nov. 1, 1943 
but of course I don't know if this is the original manual for this radio. 

Also, the phenolic wafers in the switches seem to be oily and dirty. What 
could I use to clean them that would not damage them or the other components 
near them?

Thanks 

Don