eliminating default scenery

Sorry if this already asked or written in FAQs (can't really find it)
I working on scenery one of domestic airport in my country, I have mine done and export the bgl in FS2004, now my problem is, how do I eliminate the default scenery of the airport ? when I start FS2004 to see my exported scenery, It's overlapping the default secenery...
Thank you for any help...
I working on scenery one of domestic airport in my country, I have mine done and export the bgl in FS2004, now my problem is, how do I eliminate the default scenery of the airport ? when I start FS2004 to see my exported scenery, It's overlapping the default secenery...
Thank you for any help...