Search 2.0 bottom end conversion, its fairly simple to do.
ABF is a far better choice all round has 8 more valves and ompf.
You will need all the bits to make your car a GTI first and then the looms etc.
Would be easier to buy a mk3 16v and lift all the running gear as your starting from pv spec golf.
500 will buy you a good donor car to rip apart, although some g2 parts will be needed.
Search is your friend as this has been done a lot, also go on club gti as there are some handy folk there who have done this to death.