correct me if i am wrong. but...just like the 96-98 climate controls are not interchangable with the 99-00 the same goes for nav. nav was an ek9 (99-00) option. also it doesnt matter if he has the gps disc. since we live in different regions ( i think US B and japan is C) the disc wont even load because the US wasnt even loaded into the data base. i beleive this is a gathers unit?