Have engine on the ground now. Carb off and head cover off. Exhaust valves look as I expected them to, but the back surfaces of the intake valves are pure white. Seems like it has been very hot in there to me.
Carb has a 155 main installed. Cam chain timing appears to be correct: both cam lobes pointed down, lines on cam end aligned with top of head (horizontal), and T mark aligned with pointer on housing.
Here are my questions at this point:
1. when I took the LH cover off, the starter gear and a washer fell out. I assume the starter gear is installed with the raised boss toward the center of the engine. Does the flat washer go on outside the starter gear (between the gear and the outer case)?
2. Am I correct in my assumptions about cam timing being correct?
3. Does anybody have any good theories as to why this engine continues to overheat? (Supertrapp with 8 discs installed with stock air cleaner).
Is ignition timing adjustable on this engine? That's the only other thing I can think of???? ???

I recall one fellow found that the previous owner had reinstalled the oil pump in the wrong direction... ???

Here she is with a new coat of black frame paint!
http://www.bikepics.com/photo/upload-c.asp?PID=5BBF50715A927C47

OH!  I just noticed you replace the cam chain after 5000 miles...um...I'm going to guess your bike ran out of oil at some point in its life.  Did you check the various engine bearings?  How did the cylinder walls look?