Setting a custom content width on Blogger’s Simple template

Most of my Blogger blogs use the Simple template; I haven’t got much time or inclination to scroll through masses of templates and experiment.
You can use the theme designer or you can directly edit the HTML to change some settings.
On some of my blogs I have directly edited the HTML to set a custom width of 1900 pixels so as to use the full width of my 1920×1080 screen. I prefer this width because I like to make my images 1600 pixels wide for display on the blog. 
In the Simple blog template HTML edit this section from line 583-586:

      <b:variable default=’960px’ name=’content.width’ type=’length’ value=’1900px’/>
      <b:variable default=’0′ name=’main.column.left.width’ type=’length’ value=’330px’/>
      <b:variable default=’310px’ name=’main.column.right.width’ type=’length’ value=’0px’/>
The line you are changing is name=’content.width’ and as you can see I have put in 1900px which I can only set to somewhat less if I use the theme designer interface.
NZ Rail Maps is the first blog to use this wide layout. Some of the other blogs will be adjusted as necessary.