Hey It's guitar2player and here is another Nirvana tab, not sure if it's standard or 
step down you choose, here it is...

Legend:
~ = Let ring
* = Distortion
/ = slide into

Verse:

  Am       Am  Am  Am          G    G  G   G
|-0~-------0--0~---0~----------3~---3--3---3~--------|
|-1~-------1--1~---1~----------3~---3--3---3~--------|
|-2~-------2--2~---2~----------0~---0--0---0~--------|
|-2~-------2--2~-2-2~----------0~---0--0---0~--------|x2 Distortion second
|-0~-2-0-2-0--0~-2-0~-3-1-3-0--2~---2--2-3-2~--------|  Time only
|------------------------------3~-3-3--3-3-3~-3-1-3-0|
                                              * * * *
Chorus:

|--------------------------------------------------------------|
|--------------------------------------------------------------|
|-5-5-5-5-5-5-5-5-/-7-7-7-7-7-7-7-/-3-3-3-3-3-3-3-----3-----3--|
|-5-5-5-5-5-5-5-5-/-7-7-7-7-7-7-7-/-3-3-3-3-3-3-3-----3-----3--|
|-3-3-3-3-3-3-3-3-/-5-5-5-5-5-5-5-/-1-1-1-1-1-1-1-p0-h1-p0-h1--|x4
|--------------------------------------------------------------|
  * * * * * * * *   * * * * * * *   * * * * * * *  *  *  *  *
Verse:

  Am       Am  Am  Am          G    G  G   G
|-0~-------0--0~---0~----------3~---3--3---3~--------|
|-1~-------1--1~---1~----------3~---3--3---3~--------|
|-2~-------2--2~---2~----------0~---0--0---0~--------|
|-2~-------2--2~-2-2~----------0~---0--0---0~--------|x2 Distortion second
|-0~-2-0-2-0--0~-2-0~-3-1-3-0--2~---2--2-3-2~--------|   Time only
|------------------------------3~-3-3--3-3-3~-3-1-3-0|
                                              * * * *
Chorus:

|--------------------------------------------------------------|
|--------------------------------------------------------------|
|-5-5-5-5-5-5-5-5-/-7-7-7-7-7-7-7-/-3-3-3-3-3-3-3-----3-----3--|
|-5-5-5-5-5-5-5-5-/-7-7-7-7-7-7-7-/-3-3-3-3-3-3-3-----3-----3--|
|-3-3-3-3-3-3-3-3-/-5-5-5-5-5-5-5-/-1-1-1-1-1-1-1-p0-h1-p0-h1--|x4
|--------------------------------------------------------------|
  * * * * * * * *   * * * * * * *   * * * * * * *  *  *  *  *
Solo: [all weird distortion]

|---------------------------------------3-3-2-0-----------|
|----------------------------------------------3-2-0------|
|----2-h3-p2-0----2-h3-p2-0-------------------------2-0---|x2
|--2------------2------------0-2-h3-p2-0------------------|
|-0-----------0-------------------------------------------|
|-------------------------3-------------------------------|

Verse: [quieter than the other verses]

  Am       Am  Am  Am          G    G  G   G
|-0~-------0--0~---0~----------3~---3--3---3~--------|
|-1~-------1--1~---1~----------3~---3--3---3~--------|
|-2~-------2--2~---2~----------0~---0--0---0~--------|
|-2~-------2--2~-2-2~----------0~---0--0---0~--------|x2 Distortion second
|-0~-2-0-2-0--0~-2-0~-3-1-3-0--2~---2--2-3-2~--------|  Time only
|------------------------------3~-3-3--3-3-3~-3-1-3-0|
                                              * * * *

Chorus:

|--------------------------------------------------------------|
|--------------------------------------------------------------|
|-5-5-5-5-5-5-5-5-/-7-7-7-7-7-7-7-/-3-3-3-3-3-3-3-----3-----3--|
|-5-5-5-5-5-5-5-5-/-7-7-7-7-7-7-7-/-3-3-3-3-3-3-3-----3-----3--|
|-3-3-3-3-3-3-3-3-/-5-5-5-5-5-5-5-/-1-1-1-1-1-1-1-p0-h1-p0-h1--|x4
|--------------------------------------------------------------|
  * * * * * * * *   * * * * * * *   * * * * * * *  *  *  *  *


Outro:
                 Am  Am  Am    Am     Am
|-----------------0~-0~--0--0---0--0---0------0~-|
|-----------------1~-1~--1---1--1---1--1-----1---|
|-3-3-3-3-3-3-3-3-2~-2~--2----2-2----2-2----2----|x1
|-3-3-3-3-3-3-3-3-2~-2~--2------2------2---2-----|
|-1-1-1-1-1-1-1-1-0~-0~--0------0------0--0------|
|------------------------------------------------|
  * * * * * * * * * *