I just bought a 99' F4, will the plastics from a 02 F4i fit on without any issues?

Everything except the nose cowling, as this model has different headlights. (Unless you want to get busy!) The bikes are basically the same, but with differentfuel systems and headlights.

Further to my last, the 2 piece seat unit for the f-sport model (dont know what you call it in the US) may cause complications due to electrical components/brackets under the seats.

my belief is this, i think if you want to do a full conversion from 99 to 02 fairings then it should work. tail and headlights included.i could be wrong. just download the two manuals and compare to your best abilities