Trade the car in for a similar equipped/mileaged/year manual. You should get better residual for the auto and get a manual transmission for considerably less when all said and done. Or you could just wait for your slushbox to fail and do the swap at that time.
I am uncertain as to the electronics hurdles. The only known issue I know about tranny swaps is the possible loss of the requirement to hold down the clutch on startup. Which could cause a lurch accident if you park it in gear.