With regards to leaning on a climb; wouldn't you always want the mixture to be lean of peak as compared with rich of peak?
What peak are you talking about? If you mean peak EGT, definitely not!
1) in any event, you'll struggle to get all four cylinders of an O-320 lean of peak;
2) even if you could, the power loss would make the long, slow climb even longer; and
3) because you won't be able to achieve a sufficiently lean setting, at least half the climb will in the 'red box' avoid area for mixture settings.
What you really want to do, above the first few thousand feet which should be at full rich, is climb at peak power, circa 100degF rich of peak egt.