The actual chords for Dear Brother are, in my opinion, Fm, Eb, Cm, Bb.  But because Eb 
and Cm are such difficult chords to play, I recommend:

Tune your guitar to Eb (1/2 step down)

I will write the chord names as if you were playing on std E tuning (IE Fm becomes Em)

Em             D
Reminiscing on our indestructible days
Bm
The party never seemed to end
A                           Em... D... Bm... A...
We donkey punched the night away


Em                   D
(Sin after sin) 25/7 some risky business, my friend
Bm                        A
Fortunes seem to favor us 'round every dark and twisted bend

Em (2nd time Bm)        D (2nd time A)
You can't cheat death, can't outrun the grim reaper
(repeat)

Em                           D
This glass I raise is heavy, heavy as my heart this day
Bm                                A
The reaper slipped right past us, bastard stole your breath away

(Em/drum-solo)

Em                        D
We raise a heavy glass to you in our indestructible days
Bm                       A
May heavens call to you may stars align and light your way

Em (2nd time Bm)
Farewell, dear friend
D (2nd time A)
Fare thee well, dear brother
(repeat)

Em                        D
A sad and joyful toast to you, heavy is my heart this day
Bm                             A
Once more into the breach, dear friend, donkey punch the night away