Hey Aman,
Welcome to the forum.
Thinking about this, it is not impossible but the work would be very involved. Taking out electronics from the car is one thing but adding electronics into it, hmm. Here are the stuff involved in the process I think (true for E46).
1. get an okay auto trans
2. long shaft may be needed as the gearbox length may be different
3. diff/final drive could also be different between auto and manual
4. EGS/transmission computer to control transmission and communicate with DME/engine control unit
5. Wiring harness
6. ATF cooler line
7. Pedal would be optional, you can keep the clutch pedal
8. IKE/instrument cluster I think just need to be reprogrammed
9. Installing and reprogramming (lots of it)
Not sure if anyone has done this before. You may want to consider swapping ride with another member. Cheers.
