Ignition switxh

Hi i have a 2004 grand prix. I lpst
my key. O called the lockssmith
and they say it will be 150 to 180
to come out and make a key. I
thpught that was a little to
exspensive for this car. Its my
work car. So i went to the local
junck yard and purchased a used
ignition switch with the lpck
cylinder. I cliped the 3 wires on
the cylinder of the one i purched
and the one in my car. I removed
the one in my car and wired the
new one to my car. I then
plugged in both sets of wires
and cable. Screw the ignition
back in place. Put the key in and
it cranked the first five times.
Went in the house came out .
tried to crank it and the anti theft
message came on. So i ded the
10min deal 7 times and still
nothing. What can i do?