This isn't a stalk converter type product, but it uses IR and claims to work with the 2002 s2000:

http://www.pac-audio.com/products/swi.htm

The only question is whether or not the empeg will see it... if so you could just use hijack to map the IR commands to what you want.

"The SWI-X interfaces will only work with infrared remotes that use the common 38-40kHz carrier frequency. "

Does the empeg foot that bill guys??