Lots of it :) For balance keep the mids up, one mistake many people make is they try scooping them way down like for nu-metal and the whole song comes out mush.

Welcome to the forum. I'm not a nirvana fan so I can't help with this much, but that's one of those songs that you can use any generic distortion that still gives decent note definition and it will be good enough for all practical purposes. That song not exactly a delicate work of art.

If you need tab for any part of the song I can provide, I used to play that song doing covers for small gigs like birthday parties/skating rinks.