viper 791xv with extra remote

I have a Viper 791xv with remote 479 V/P/C

My issue is that my 479 V/P/C is falling apart and I've had to solder connections on it once. 

I purchased a new remote, one that has the program button on the backside  it is a 479 V/P/X

I would like to keep the one that is falling apart 479 V/P/C as a backup.

I've tried the following

1. Open drivers door.

2. turn on ignition

3. within 10secs press the valet button once.

4. press and hold valet button. (makes it chirp once)

5. press the unlock button on the new remote ( just beeps with the no signal icon flashing)

6. the alarm then blows off to weeeooo weeeooos

could someone please tell me how I can program these so they can both co-exist.

I've read through the owners manual and the installation manual.

I found out what my problem was.

In step 4 I didn't continue to hold the valet button after it chirped once.

So once I held the button in waited for it to chirp once at me. I then hit the unlock button on my remote and it responded back to me.  I then let go of the valet button and turned the ignition off and all was well :)