I have the following upgrade kits:
Area 51 / Max Force combo (Upgrade from single game to dual game)
25.00 shipped for security chip and 65.00 ship for entire kit (security chip,eproms,harddrive)
NFL Blitz 2000 Gold (Upgrade any Seattle Boardset-Blitz,Blitz99,Carnevil etc..)
35 shipped for security chip and boot eprom, or 70.00 shipped for security chip, boot eprom, and harddrive