The only Baseband Version that can be Unlocked for the iPhone 4 is 01.59.00. However, A Gevey SIM card would Unlock the iPhone 4, whether the Baseband is higher than 01.59.00. Any Baseband, any Firmware, would work. I don't know If the Gevey SIM will work in India. Because you need to dial 112 (as followed in the Instructions) to unlock the iPhone.
The 112 method works in any country. Also if you are planning on using an Indian sim, then you must perform the steps in India, with the new sim installed and with the signal readily available.