Remove Column

Hey there @ageingdj – I’ll answer your questions separately:

1>Is there a way to remove/hide the “Edit” column on the left of the posts? – this will centre the images.

Only logged-in users see the word “Edit.” I think you mean the column where the category is displayed. This CSS should remove that column and also widen the main column on single posts:

.single .entry-meta {
  display: none;
}

.single  #primary {
  width: 100%; 
}

Don’t edit the theme files directly, otherwise your changes will be overwritten every time the theme is updated.

An easy way to add custom CSS is to use the CSS editor included in the Customizer as of WordPress 4.7. Head to Appearance > Customize > Additional CSS to add your custom CSS.

Sorry for the delay in answering the second part of your question – I wanted to get a second opinion on something before replying.

2>How do I increase the size of the images/galleries on the posts?

Widening the content width (i.e. for images and galleries) should make them fill your new content width – that’s why it doesn’t look centered now; the column width has changed, but you haven’t yet widened the width of the galleries and other media

In order to change the media content width, you’ll need to first create a child theme, as this can’t be done with CSS alone. You’d then add this to your child theme’s functions file:

if ( ! isset( $content_width ) ) {
    $content_width = 882; /* pixels */
}

I took the new content width from the new width of your single posts page.

You may need to run a Regenerate Thumbnails plugin if your site doesn’t pick up the new width right away. I just tested in a Harmonic child theme and the gallery’s width updated right away.

An alternative to a child theme is to put the same function in a functionality plugin instead.