I got free dish and I was wondering if I bought a 508 (from the Dishstore of course if I could swap it out with the 301 I got with the plan. I know I have to probally have two active receivers for a year since that's what I signed up for but was wondering if I could just swap out the 301 since I don't need it right now and use the 508 with my 811. Is this possible or would I have to just activate the 508 and keep the other two recievers?