05 suzuki forenza motor swap

I have a 05 suzuki forenza with a 5 speed trans. The motor is lockup and I have found a 05 suzuki forenza with a automatic . I have been told that this motor will not work in place of the 5 speed. I would like to know if it is possible to switch any components to make it work. Any help on this would be great

The only thing different should be the flexplate on an auto, vs your flywheel in the 5 speed. If you are only changing the motor I don't see why it would not work.