2000 RX300 towing wiring help

I got a 2000 RX300 AWD that came with the Towing Prep Pkg/Trans Oil Cool.  However, I could not locate the trailer wire connector, I have search every lexus/toyota forum that I could find and no post regarding to the 2000.  However, I have found lots of post for the 1999 and 2001, so far, I have follow these post and take apart every posible liner in the trunk where spare tire locate and still cannot find the trailer/hitch wiring harness  any where.  Any tip would be greatly appreciated.

thanks,