OK, I took a picture of this setup today. The filter is a K&N RE-0810 which I bought from Conley's performance at the GSCA Nationals (~$45). It fit's perfectly where the stock air box was and uses the factory accordian duct. (This is in my '82 GN)
http://www.beforeblack.net/images/cone82.JPG
And here's another version from my '83 T Type. This time I wanted to keep the stock air box in place in case it gets cold enough that I need the THERMAC for daily driving. Something has to go so the cone can fit, so out came the charcoal cannister. Since the accordian isn't long enough, $3 worth of dryer duct does the job.
http://www.beforeblack.net/images/cone83.JPG