Tuning for economy

What would be the best approach for economy tuning. (eg: reduce fuel consumption for transportation vehicles)

Set the timing up for MBT, or as close to without inducing knock, and run a lambda ratio of about 1.03 at various cruise speeds. (e.g. in my state of NSW in Australia we have 40, 50, 60, 70, 80, 100, and 110 kmh speed zones so in these zones cruise speed is related to the speed limit).

My general guide is to lean out the AFR in cruise areas of your map until the torque drops by 10%. If you go further than this you will actually need to open the throttle further to get produce enough torque to maintain a cruise speed and hence your fuel economy actually gets worse.