Recover an XBOX Gamertag for and old email account

Question

I recently had my Xbox 360 die on me and went to Best Buys to use the 2 yr warranty AGAIN for the 4th time. As usual Best Buys has held up to their end of the bargain and replaced my Xbox 360. Only this time they upgraded me to an Xbox 360 Elite. This is the first time I did not keep my old hard drive because the elite HD is much larger. When I got home and reconnected everything and tried to recover my gamertag I needed the original E-mail and password to do this.  That was about 4 yrs ago and 2 ISP's ago.  I am not sure if I remember the Email from back then and I certainly do not remember the password I signed up with.  I tried contacting Xbox by phone (4 Times) and each time they get me to go online and fill out a form with all the personal information I can think of to prove I am who I say I am. The reponse I get tells me that the information is not complete and that the old   E-mail Windows live account doesn't exist. I do not want to cancel my Xbox Live account because I have made purchases with this account and do not want to re-purchase them. I don't even know if I can cancel it without the email and password...???

What do I need to do to get my Gamertag back?  I gave my name, gamertag, SSN, Address, Credit card number I am paying for it with including expiration date, The answers to 3 secret questions, the amount of microsoft points I still have on my balance, friend's names on my Xbox Live account and offered to answer any other questions they want to ask me.  

What now?