Took carbs off my '73 CB500k, put new float needles and seats in, adjusted float levels, downsized main jets from 100 to 98. Got carbs back in without any blood.
In spite of all this, I think the best thing I did to solve my variable idle problem was to use some Yamabond on the intakes. The o-rings seem to be a bit undersized and I think there were some vacuum leaks there.
Anyway, she started right up, and my initial test ride was good!
Also stripped paint off tank in prep for painting!