CAR ONLY CLICKS, WIL NOT CRANK UP WHEN TURNING KEY, THE LIGHTS AND RADIO COME ON I CHECKED THE BATTERY AND IT STILL WILL NOT START

Get the charging system checked. Battery might be run down, but is probably okay if its only a week old. But have your mechanic check the connections at the starter, which was removed and replaced during the tranny work. Could be as simple as that.

With Any electrical problem check the battery cables First! They are often forgotten after major work or can loosen up. If they are tight then move on to the other excellent options mentioned

My car started doing same thing couple weeks ago. Dash comes in so does radio. My stereo was jacked out of it what could be my issue

I had the same problem just recently. Oddly enough, it turned out that The A/C Compressor was completely Locked up so and there was no crank... Before figuring this out, I ended up replacing the starter, switched out the battery and was about to change out the ignition switch and module. My neighbor told me to try to crank the engine by hand using a Socket and pry bar. Freaking thing would not turn. I took off the Serpentine belt and tried it again and there was no issue. I checked to see what was and wasn't spinning and the A/C Compressor was the issue. Hope this helps and good luck.