First off, this is my first ever solo i've attempted to tab out, so go easy on me.
 I've only tabbed 1 song before, and it was quite sloppy and pathetic to be honestly, so 
may not be the best.
But hopefully it'll give you an idea of how the solo is played.
Last, I tabbed this in standard tuning (EADGBE). I believe The Showdown plays in D 
or Drop C, so you can adjust
on the neck accordingly.

|---------------------------------------------------------|
|---------------------------------------------------------|
|----12-14b~--14p12h14~--12-14-16-12-14--12-14------------|
|-/14----------------------------------14-----14br--------|
|---------------------------------------------------------|
|---------------------------------------------------------|

|-----------------------------------------------------------|
|-----------------------------------------------------------|
|------12-14-16-14-12-----16b~--14-16-17-16-14-17-16-14-19*-|
|-12-14--------------14-12----------------------------------|
|-----------------------------------------------------------|
|-----------------------------------------------------------|

|------------------------------------------------I think they use-----|
|-----------------18b*-18br*---------------------whammy on the 11 here|
|--------9-12-9~-------------14h16p14-12-14-12~-----12p11-------------|
|-9-10-12----------------------------------------/14------------------|
|---------------------------------------------------------------------|
|---------------------------------------------------------------------|

|-----------------------------------------------------------------|
|-----------------------------------------------------------------|
|-/11brbrbr-9~----------------------------------------------------|
|--------------------------------------------------12----------14~|
|---------------12--------14-12-----15-14-12--15-14----15p14p12---|
|-----------------15-14-12-----15-14--------15--------------------|
PM               . .  .  . .  . .  . .  .  . . .  .

|-----------------16h17h19p17p16---------|
|---------16h17h19---------------17/19~~~|
|-15h16h18-------------------------------|
|----------------------------------------|
|----------------------------------------|
|----------------------------------------|

Being my first solo i've tabbed, this was quite difficult, particularly the palm muted 
Please rate and comment! Enjoy!