Jim,

50 RPM drop on the rich side is too rich at cruise...

RPM doesn't matter.

50
degrees rich of peak on the EGT is about right with a carb.

Why? How? 50 ROP is the point of maximum internal combustion pressure.
A point at which you don't really want to be.

With fuel injection, just a little below peak or even at
peak if the cruise power is set below 70%.

below peak on the rich or the lean side? A limit of 70 is artificial.
65 and 75 is mentioned by the engine manufacturers, respectively. Many
say those limits don't mean that much. CHTs do. Many people run their
engines lean of peak (well lean of peak) at 80 percent and more. CHTs
stay well below 380.
There is no difference in leaning technique between carb'd and injected
engines.

At low power
settings you can run at peak since the actual temperatures
will be low.

What temperatures? EGT? CHT? Actual EGTs don't matter anyway. Actual
CHTs are higher ROP than they are at peak EGT. They shouldn't be above
380.

If you have a calibrated EGT (TIT) follow the
limits.

Absolute EGTs don't matter. TIT is a different story, since the engine
is turbo'd.

I really recommend reading Deakin's columns at Avweb - it makes you see
several lights real quick.

--
Thomas Borchert (EDDH)