You need to know exactly every last piece of hardware and software. A list of all warranties and licenses should be assembled. Each shop must consider exactly how to do this. There are Out Source Vendors with Knowledge and Tools. For many well run smaller shops, this stage may be very straight forward.
Many Vendors know where the problems are and can help.
In this step, the Source Code is critical. It should be obvious to anyone reading this that the following lie in mutually dependent loops. This organization will only allow Year 2000 Compliant Companies and Computer Professionals to witness the Year 2000 Super Bowl. Let us assure you that for all others there will be no Year 2000 Super Bowl. Many older programs do not even recognize the Leap Year Day in 2000.