Templating question

Hi, I may be asked soon to migrate a 80+ page site using a really old twenty eleven theme (without menu support) to a new mobile responsive theme and I'm picking squirrel because without the homepage, its standard layout is similar to my clients current site. My question is that the current 80+ pages does not use any sidebars, all are fullwidth in a box layout, can you think of an easy way (without changing each page manually to fullwidth template) to change the default right sidebar layout to the full width tempalate. I easily see the fullwidth-template.php in the theme files, and I'm hoping I can replace default template code with fullwidth-template code, but don't see the default template?

Any thoughts would be appreciated, thanks.

 

Thanks, your link was broken, but I found the select all edit in the all pages view which I assume would have been what it would have shown, thanks.

 

Now after nicely switching all pages to fullwidth template every image on the pages from thumbnails and every size up displays as 100% wide and fills the entire screen, but if I use default template (which I dont want to) then thumbails, medium images and their alignments show correctly. Even a right justified thumbnail displays 100% wide (looks fine on mobile, but looks really bad on all other devices. Any ideas, thanks in advance

http://www.peterschemical.com

 

Ok, I discovered that if i change the width: 100% in your code below to width: auto; if seems to work correctly, but I'm not sure if this is OK and whether or not it may cause other issues down the line. I do notice that with this new code, images in mobile view keep there alignment (left, right) even in mobile instead of sliding underneath, but I can live with this versus the previous super huge images..... any thoughts?

.main-content .fullwidth img {
max-width: 100%;
width: auto;
height: auto;
display: inline-block;}