Keyless Pad Personal Code Problem???

[jvest]

I just bought a 2005 F250. I try to follow the instruction in the manual to set my own personal code using the 5 digit code on the plastic card. The factory code works, but I can't seem to get my personal 5 digit code to take. I even pulled the manual on my wifes 06 five hundred and that didn't work either. These are some of the procedures I've already tried.
1: enter factory-press 1-2 within 5sec-enter personal code
2: enter factory-press 1-2 within 5sec-enter personal code-press 1-2 again
3: enter factory-press 1-2 within 5sec-enter personal code-press 7-8 & 9-0 at same time.

Any suggestion?????

Thanks,
Jim