CBeyer,
It sounds as though you are using old Inter-Tel terminology here so I am not sure if you are working on an Axxess with old Inter-Tel phones that used the 7+8 to program them to look at an IPRC [IP Resource Card] or if you are working on a MiVO-250 with 53xx series phones.
If you are working on an Axxess then the 53xx series phones won't work on it as MiNet phones.
Thanks,
TE