is it possible to change the fairings on a 98 YZF600R to R6 Fairings? i love the styling of a R6 but im getting a great price on the 600R. and if i were to get exhaust would i get R6 exhaust or 600R exhaust?

No.

R6 fairings won't work. These are two different bikes, with two different frames. Where the threaded bosses on the 600R frame are, there won't be any holes in the r6 fairings. And likewise, where the holes in the fairings are there won't be holes in the frames. Also the upper bracket which holds the upper fairing and speedo aren't the same size or shape.

So unfortunately unless you want to do a huge hack and fab job on a good set of r6 plastic it isn't going to work.

Also as far as your exhaust goes, you would buy an exhaust for a 600R. Regardless of what plastic is on the bike, it's still a 600R.