There is a GNX book on ebay. 547 made Don't Know what number it is.
eBay Motors: Buick Grand National GNX Hardbound Book RARE!!! (item 130266544254 end time Nov-07-08 14:02:31 PST)
eBay Motors: Buick Grand National GNX Hardbound Book RARE!!! (item 130266544254 end time Nov-07-08 14:02:31 PST)