Audi/Bose Radio System Replacement

[Michael Palatas]

Alright guys, here's my problem, the factory stock Audi/Bose radio system in my '91 200 20V TQ sedan has finally bitten the dust.  I want to gut the system and replace it with an new aftermarket system (head unit, speakers, amps, etc...).  I know some of you have done that (taka at a minimum) and have some questions:
   
  1.  What speaker dimensions are appropriate for the existing openings after the old stuff is removed?  
  2.  Has anybody ever tried to install some speakers (tweeters I assume) into the dashboard speaker openings; and what size would fit?
  3.  Do you have any suggestions as to some of the best speakers and stereos out there?  Right now I am using Crutchfield.com to find ones that fit and they have been very helpful, but they have so many choices...
   
  TIA!
   
  Nick
  103K, Stage III, Eurolights, 17' wheels, Faze boost gage.