"""I have a 2000 316i saloon. I want to convert the front end to 2001-present spec ie, new grille and lights. is this possible; if so how much roughly would it cost.
Yes it is possible. Remember you need to get a 2001 and up Hood with the 2001 and up kidney grills. , Left and Right Fenders, Whole headlight assembly including parking lights and side markers. It probably going to cost you about $3000 US.
Instead of doing that, I would just get an Mtech II front bumper. You will be amazed and suprised of how much it changes your car.