I am finishing my basement and I want to buy a 501 or 508 from ebay or Dishstore.net and add it to my setup. Right know I only have One 510 that replaced my 311 which I still have. If I buy the new one will E* add it to my account with no problem? Or should I re-activate the 311 in the basement and then buy the new one and have them replace the 311 again?