From: Chicago, Illinois
You can't starve them out, not in a reasonable timeframe.
The primary thing is to bring enough troops. Five Divisions is the minimum for a quick conquest. Minimum usage should be:
2nd Division (100% prepped for Singapore turn 1)
1 other Division (21st from Shanghai, or 38th from Hong Kong)
All these units, with the exception of the 38th Div, should be prepping for Singapore starting TURN 1. Any fighting the Allies do up the peninsula, while you are not prepped for it, ultimately does you a favor.
That is the bare minimum; I would go 6-7 to be sure. You can lift a couple more from Luzon, if the Allies are driven back on Clark. Starving out Luzon is the correct option there; it is NOT in Malaya.
Others have stated the rest: Bomb the base to prevent fort rebuilds, and knock the forts down gradually.