Hi are you sure its a charging issue? Does your battery go flat if left for a period of time, indicating a leakage issue?
Another thing i noticed when reading this is that Neil stated the field coil resistance to be 4.0 ohms, but you have stated it as
"Resistance reading from green/brown (brushes) at connector was .1/.2 . "
... Which would indicate either a short circuit there, Or you didnt put a slip of paper between the brushes and slip ring and had the connector block plugged in. Or that i have mis-understood what you are saying here, because this should be the field coil resistance figure you quoted as
"Field coil resistance should be 2.7 to 3.3 ohms. Is that what I should be getting from the brushes?"
Also did you do any testing to ground (chassis) from all coil connections field and stator, switch meter to maximum resistance reading, black lead to the steel body and red lead to coil connections, expect no reading, any reading is an insulation breakdown.
Next, your voltage regulator is a moving contact (relay) type yes?
Remove the cover and check the contact have not stuck and are free to move also clean the contacts with a petrol soaked rag, or if they look burned use a strip of fine emery or medium wet / dry to clean them, Although they can get so burned they are un useable and a replacement would be needed in extreme cases.