Finally! We are US citizens.
Thanks for everyone's help.
They just need GC, oath letter, and any other INS/BCIS issued documents like reentry permits (white color passport like document), etc.
Oath ceremony went fine. There were a total of 100 people naturalized at our ceremony. The whole process took around 2 hours (11:30AM - 1:30PM).
Good luck to everyone else.
Next, need to apply for US passport and Indian visa/PIO (haven't decided which way to go yet). Any advise from the group?
Thanks again and good luck!