Have you looked at the AutoSlim package?

Have you tried the MinimalFortran package yet?

https://github.com/315234/MinimalFortran

I just looked it up on the excellent page provided by the awesome wbond  

http://wbond.net/sublime_packages/community

and it appears in my list of available packages through PackageControl (also provided by wbond whose place in the pantheon of the great is assured)

Go to this file:

Packages/User/Base File.sublime-settings 

Add this line:

"rulers": [0, 4, 8, 12, 16]

Locate this file:

tab_selected.png

Make a copy of the current file as a back up. (Always give yourself the chance to easily roll back changes in case your changes are not as good as you hoped.)

Now open the file in your favourite image editor and change the colour as you feel is best. As you save the changes to the file you should see the change in Sublime Text 2. If not then close and restart ST2 to see the changes.