Hi Sean,
I've just gone from the stock 19/55 sprockets 428 chain to 15/47 sprockets 520 chain. I bought a 110 link chain and had to remove 2 or 3 links to fit it so a 108 might do you. Personally I'd go for the 110 link chain because you know it is going to be plenty long enough.
One thing to be aware of is that the Renthal front sprockets are only 6mm wide and the original sprocket is 9mm wide. You'll just need a 1.5mm washer each side to compensate for that. I bought a big bag so if you go ahead let me know and I'll post you some. The 47 tooth rear sprocket was only available in the UK in hardened anodised steel by Renthal. There are plain steel versions around but they're more readily available in the US than the UK I think.
I can't recommend this set up enough the bike is a real joy to ride now. Plenty of acceleration and so much better for riding round town if you do any commuting. In town traffic it was difficult to get a gear that it was happy in but now it deals with the 20 and 30 restrictions with no dramas. Hardly have to feather the clutch at all because it just responds so well in the low gears.
I had new tyres front and rear which were a Bridgestone Battlax BT23 front and BT92 rear. A huge improvement over the old ones.
If you need any parts try these people, they own FZRs and know what works best with each model:
http://www.projection-components.co.uk/