My golf was a gti 16v when i had it.
First conversion was to a 9a with kr cams and 6 hours to do the conversion with good power increase.
Now i have just finished a 20vt done it myself and running 230bhp on k03s. Much better to drive than my old mk3 vr highline. Conversion was not that hard realy just got a couple of things to finish off. In total the conversion cost me £2500. I would say best conversion for the mk2.