byez,
My recommendation - put 12oz Neutra 131 (from Schaeffers) in for 300 to 500 miles (have XXw40 wt in the crankase). Follow immediately with a 20 min. Amsoil flush. I did this and immediately dropped my oil consumption in half (I apparently had gummed oil rings). That's it.
When I did this previously I chged out the oil before the Amsoil flush, but I don't think that's necessary. Just start w/ a heavy wt oil - Run the Neutra, run the Amsoil Flush, drain. The Neutra will do much of the cleaning and soften things up for the Amsoil flush to do the final purging.