F-16 is made by Lockheed Martin & F-18 by Boeing. Boeing has very good relations with India. They have bagged orders for C-17, P-8I, Apache, Chinook. GE is also making F-414 engines in India for Tejas. So it is very easy for Boeing to just transfer the assembly line to India & make the body. Electronics can be imported.
Infact given the price of Rafale, India will choose to buy F-18.
Maybe...