I am not able to adjust the bias voltage to the
specified level. It stays at around 3v. The oscillator
will work occasionally, and I tried cleaning the switch
to get it more reliable with some contact cleaner and now
I cannot get it to work at all with the case on.

Paul-

Although I was happy with the power supply modification, I wasn't happy with
the way the oscillator turned out.

One thing you can try is using the contact cleaner on the contact blades to the
rotors of the tuning capacitor. It seems that at least one of the two rotors
is insulated from ground, so both sets of contacts need to be clean and have
good tension.

Problems I encountered include not oscillating, distortion and frequency
errors, all at different frequency band and dial settings. I never was able to
make it perfect (or even meet specs), but got it to work fairly consistently.
I plan to take another look to see if adding capacitors across the zeners might
help. That sounds like a good idea.

73, Fred, K4DII