Okay I'm wondering, since you JUST had the transmission done, if your gear shift lever is "off" and is not going fully into Park.
Here's a description of how the system works in your car:
"COLUMN LOCK CIRCUIT DESCRIPTION
The steering column electric park lock prevents the ignition key from being turned to the LOCK position from the RUN, BULB TEST, or START position, when the transaxle is in a non-PARK position. Once the vehicle is shifted out of the PARK position, the park position switch opens de-energizing the steering column electric park lock.
The mechanical lock within the ignition lock cylinder disables the ignition key from moving so the key cannot be taken out of the cylinder. Battery voltage is supplied to the park position switch through circuit 1600 when the ignition key is in the RUN, BULB TEST, or START position. When the shifter is in the PARK position, the park position switch within the automatic transaxle control closes, supplying voltage through circuit 1134 to the steering column electric park lock energizing it. When the steering column electric park lock is energized it pulls the mechanical lock in the ignition key cylinder away from the cylinder allowing the ignition key to be turned to the LOCK position and be taken out of the cylinder.