There's a couple other things I'd like to know such as how far is remote #2 from the receiver...they only work up to a certain distance. Do you have another UHF remote in the house like a 322, 510, etc... or another piece of equipment (stereo or something) that uses UHF to transmit. By moving the antenna, what do you mean? Did you put a short piece of coax between the antenna and the input? This often helps if your distance is too far.
But to answer your question,
Put the antenna back on the receiver if you have it off
Bring the #2 remote to the receiver area
Get into the system info screen - do this by either pushing the Sys Info on the front panel of the receiver or by pushing MENU, 6, 1, 3 on the #1 remote (the green one).
Once looking at the system info screen, grab remote #2 and hold the SAT button until all the lights light up on that remote. Let the button go and SAT should blink.
Now punch in your new number (1-16 - there are ways to go up to 32, but thats not needed). Say your new number is 10 then punch in 1 then 0; now hit the # (pound) button - the remote should blink 3 times. Point the remote at the receiver and hit the "RECORD" button on the remote (remember all this latter stuff to be done on remote #2). You should see the Secondary remote address change to your new #.
Go back to remote 1, and select done, then 0 until your watching TV...take #2 to the other room and test it out.
Note that if you have anything else that is UHF, especially another dish receiver, you MAY change its address as well.