sorry if this may has been covered i searched and am not 100% sure of the answer so here it is.....
just got a 99 600 f4 it has some cosmetic damage. i figured i would change the fairing out with newer ones. my question is what years will fit itand also what year subframe will fit. thanks in advanced

 

Any year side fairing will fit.

The tail fairing on the 99/00 showed up on the later versions of the F4i (after the RR showed up)

The upperfairing will only fit from a 99/00 F4 - the F4i gauge cluster and headlight are different. If you want an F4i upper you'll need to do a guage swap, headlight swap, and then figure out the wiring of the gauges. It has been done.

The subframe is different between the bananna and split seats. To keep it simple just stick with the bananna seat... unless you REALLY want to source the split seat, subframe and plastic.

This all depends on budget.

What's damaged - how badily is it damged? Unless it is destroyed you are probably cheaper to patch it up, buy the $100 decal set from ebay, and have someone paint the bike. It is all solid colours so it's not hard at all. Could be in the $300-400 paint range... or just do it yourself. I've seen some spectacular spray bomb results.