macham copy my service 20 route from pasir ris to kent ridge.
difference is that is operates from the north east instead of the
east. 
I suggested a route once in this forum or in MSN. I now have a
newer/updated/better version of it.
Service 85 (PUN - BSH)
Punggol Int, Punggol Central, Punggol East, Punggol Field, Punggol
Rd, TPE, CTE, AMK Ave 5, AMK Ave 8, AMK Ave 3, AMK Ave 6, Marymount
Rd, Bishan St 22, Bishan Rd, Bishan St 11, Bishan Int.
It seems to copy parts of 54 88 159.