Okay, this will be probably be basic for most of you, but (although I wasn't a Marine [happy bleated birthday, btw, Devil Dogs!]) I need slow talking and lots of pictures apparently. What I'm looking for is a step-by-step for LOP ops. I think I have the basics, but I have a question about the last step, if there even is one. My plane (Seneca III w/TCM TSIO-360s) just came out of annual and I had an Insight G4 Twin engine monitor installed with hopes of trying some LOP flying. Before the G4 I had nothing but the factory gauges and additional EI gauges which were one cylinder measurements only. I've read the Mike Busch books and John Deakin's webpages. Here's what I have so far. 1. Get to cruise altitude. 2. Do a rough lean to a couple of gph greater than expected. 3. Set MP/RPM to selected cruise. Let's call it 28"/2500RPM. 4. Let the plane stabilize there for 5-10 minutes. 5. Pull the mixture through peak EGT to LOP and pull until the EGT of the warmest cylinder is ~50° LOP. Here's my question. What do I now do with the MP? Obviously leaning the mixture had an effect on the MP. Do I just leave what I have now after leaning? Do I now reset my 28"? If I reset, am I now no longer 50° LOP? What do you smart gals and guys say? What am I missing? Thanks! Edited for clarity re: CHT and leaning.