You will need:
Mods to the wiring harness for the 13 lines to the trans
The PCM needs to be flashed for the 4l60E version
Not sure but possibly different length drive shaft
Just my opinion, but I would suggest selling it and buying another one with an Automatic. Probably $2000+ in parts plus labor and your car will not be worth any more than it was. There is a strong demand for manual transmission cars.