Following up on my previous post, if you're at 11,500 feet and 2450 RPM, it seems like there is good reason to want to run at or near best power mixture settings (around 50 degrees rich of peak EGT)  since the %power at that altitude and RPM around 60% of max HP.  It seems like you shouldn't have to worry about mixture settings causing temperature probelms at such low power conditions, and in fact, the lean-of-peak guys say as much (see the links below).  So it seems like the question boils down to whether the oil temp and CHTs you cite are too high, and if so, what should be done so that you can run at best power mixture conditions under the the relatively low power conditions you cited.

I'd sure love to be educated about this, and my guess is that the Advanced Pilot Seminar guys who Skip cited know as much about this as anyone.  There have been threads about this over the years on the LML.  John Deakin, one of the guys involved in the Advanced Pilot Seminar (or at least who used to be) wrote four short articles on leaning in the Pelican's Perch series at avweb.com that discuss the effects of leaning on CHTs.  See

http://www.avweb.com/news/columns/182179-1.html
http://www.avweb.com/news/columns/182176-1.html
http://www.avweb.com/news/columns/182583-1.html
http://www.avweb.com/news/columns/183094-1.html