Various 96 A6Q questions

[EHoeffs@aol.com]

Hey guys. I just got this car and have several questions. Thanks in advance 
for your help. 

1. My car is not equipped with any winter package items. I am interested in 
heated windshield nozzles and heated door lock. Can they be retrofitted and 
how easy is it?
2. Can the fog lamp bulbs be upgraded to 100W without damage to the glass?
3. Is 23 MPG normal on a long trip traveling 70-80 MPH?
4. Can Keyless entry be retrofitted?
5. I was told that there are no aftermarket CD changers for the non-Bose 
system.  Dealer only? I only want a changer that will work with the factory 
controls. Dealer quoted me $620.
6. My owners guide says that the passenger side mirror will "dip" when the 
car is put into reverse. Mine does not. Any suggestions on a fix?
7. I will be moving to Minnesota in a few months. Any snow-tire 
recommendations?
8. Will snow chains be necessary with the Quattro system?

Thanks for all the help.

Erik Hoeffs