I have the same cam and I installed an IAC Adjuster , made a big difference in the surging.
Mine idles between 700 and 800 pretty smooth, no more dying at lights. It is an AOD.
IAC Adjuster: http://www.latemodelrestoration.com/iwwida.pvx?;item?item_no=LRS-9939A%20%20%20%20%20%201&comp=LRS...