Not a lot online, perhaps
http://www.yamahafz1oa.com/fastfranksvalvecheckadjustmenttips.shtml maybe of help?
I used the Clymer manual which was much more detailed than the Service Manual.
You'll need to order the ignition rotor gasket as it invariably seems to break when you try & remove it.
If you're referring to the gasket with the 'half-moons' that goes between the top cover and top of the cylinder head, then no, if careful you should be able to take it off and reuse it, probably two or three times - seems fairly robust.
The top metal coolant pipes are held in place with allen bolts (obscured by rust & corrosion) and when you pull them up & out all the rust / dust / clag flies everywhere. If you can get a mini-vacuum in around them try to lift the excess off before using some wet-wipes. Those metal coolant pipes will have a gasket O-rings in underneath them and you
should replace them: nothing worse than reassembling the top end meticulously, just to see fluids making a bid for freedom...