Vert, welcome to the Forum! Get the family in here with you.
We've had 3 transplants of HUD'* so far. One on a 1990 SSE nearly 3 years ago, and 2 93 SE'* if I recall.
Shouldn't be any more difficult on your 2000, just different. I'd love to see you do it.
I'm addicted to the HUD in my SSEi, and plan to add one to my 95 SLE/SC next year. To do it right, you really need a full donor SSEi to get it all from including the dash and bezel, not just the HUD. The windshield may be a problem, but there are solutions easier than replacing it.
We'll talk about this soon, you and I.