"Grandaddy's Gun"

When Aaron Plays this live he tunes the guitar down a half step. He plays G,C,D, 
and Em throughout the whole song but he plays an odd variation of all of them that 
includes his pinky and ring finger staying in the same spot throughout the 
entirety of the song.
These are the variations of the chords that he plays:
                           E A D G B E
                        G: 3 2 0 0 3 3
                        C: 0 3 2 0 3 3
                        D: 0 0 0 2 3 3
                       Em: 0 2 2 0 3 3
what he does is he just keep his ring and pinky fingers on the 3rd fret of the b 
and little e strings through the whole song and switches only the other fingers. 
It gives the chords a brighter sound when he plays them. So throughout this tab 
when I say a chord I mean those ones up there.

G
It sets above the mantel on a couple rusty nail
C
It's not worth a lot of money
G
but it damn sure ain't for sale
D                                C
The good lord only knows all the stories it could tell
                  G
My Granddaddy's gun

G
He bought it new out of the sears and robuck catalog
C
And it shot a many a shells over the back of an old bird dog
D                                         C
And it backed a burglar down when grandma took the safety off
               G
Granddaddy's gun.

[Chorus:]
C                       G
It's just an old double barrel twelve
D                           Em
The stock is cracked and it kick's like hell
C                     G                  D
It wouldn't mean what mean's to me to no one
C                                       G
Cause I can still hear his voice when I put it to my shoulder
D                                 Em              
A gun's like a woman son it's all how you hold her
C                        G                D     
He taught me a whole lot more than how to hunt
C                          G                D                                       
And one of these days I'll pass it on to my grandson
                  G
My Granddaddy's Gun

G                                 
That old man gave it to me on the day I turned thirteen
C              
With a half shot box of shells and a kit to keep it clean
D                                    C                   
I keep a picture in the case of that sweet old man and me
                   G
And Granddaddy's gun

[Chorus:]
C                       G
It's just an old double barrel twelve
D                           Em
The stock is cracked and it kick's like hell
C                     G                  D
It wouldn't mean what mean's to me to no one
C                                       G
Cause I can still hear his voice when I put it to my shoulder
D                                 Em              
A gun's like a woman son it's all how you hold her
C                        G                D     
He taught me a whole lot more than how to hunt
C                          G                D                                       
And one of these days I'll pass it on to my grandson
                  G
My Granddaddy's Gun

C                                         G         
There's a long beard hanging on the livin' room wall
D                              C               G   D
That I got with a box call and Granddaddy's gun
C                                   G                              
There's a Shot up sign out there on forty nine
D                             Em             C               G   D
That me and billy joe shot up one night With granddaddy's gun

G                           
It sets above the mantel on a couple rusty nails
C
It ain't worth a lot of money but it damn sure ain't for sale