<<The right mag ran a little bit rough.  The left mag was smooth.
Any suggestion what to do next?  I am committed to aggressively pursue
this.>>

Are these mags pressurized?  Mooney had lots of high-altitude problems until
they pressurized the mags.  One way to check is to reduce the plug gap a bit
and then see if it still acts up.  The idea is that it might be cross-firing
at the distributor.

Gary Casey