Q: Gears won't shift

Hello. There are several things that can cause this. You need to start by checking to see if the shift linkage is moving on the transmission when you try putting it into gear. If not then the linkage may not be properly connected. If it is moving then check the bolts that connect the flywheel to the torque converter. If this were not installed then this will happen. If those are fine then the front pump of the transmission may have been damaged during the installation. I would typically check the transmission pressures with a pressure gauge if everything else looks fine. If you plan on having this looked at, consider using YourMechanic, as a certified mechanic can come to your home or office to diagnose the issue with your gears.