You remove the TOP cover on the rear head, then you remove the next set of bolts, not the HEAD bolts but the ones that go through the part of the cover below the top, this is whats leaking.
The gasket is a typical paper sort of thing, the replacement is a thin aluminum or other soft metal.
Did them on a Sportster and a Buell, I decided if HD couldn't make a damn gasket by 2000 I wouldn't buy them anymore. You need a shop manual, its a big help.