There have been a good amount of threads about K&N filters, I think it was r80rt who suggested E-mailing them and letting them know there is a demand for such filters. I had done just that and had correspondence with Thomas Walden there at K&N who gave me a direct web link for requested/suggested products. So if you are interested in having K&N air filters for the G5/C5 "UCE" engines, please take 2 minutes and fill out the short request slip at this site-
http://www.knfilters.com/products_neededSuggestion-Maybe Kevin could book mark this thread so it stays at the top and doesn't get buried