MO,
My Lionel directions do not limit the engines to the same exact product number, if that is the case that changes everything. I can now see why you are questioning my post. By the way the directions are written I believe the engines can be paired together using any of the LC & LC+ type Engines, simply by programming them separately then setting them joined on the Tracks and running them joined as a double header at the same time. If this is not true Lionel needs to clean up their directions.
PCRR/Dave