Congratulations!
I am very close to ordering one myself, prhaps as soon as this weekend. Dealers tell me the same thing, eight weeks or so - in my case (living in the great white north) I really would not want it to arrive much earlier than that. I am OK with even May delivery, as then get six months before worrying about stuff like winter tires, etc etc...
Please provide more details of you new 'Stang, like options etc...
Congrats again!