Thinking out loud, probably the best way is to search returns for each sector, find the most cost effective YUPPs and then choose those flight numbers on a multi-city (assuming the same flights are available on multi-city).
Getting close to $1 / SC is not easy else everyone would be doing it. However for those dedicated SC runners it is possible to retain QF WP (1,200 SCs) for around $2,500 and 6 - 8 days of sitting / sleeping in aircraft seats, including the trip across the Pacific in a Y exit row. Doable but enough said.