What is the best way for showing a grid of customer logos?

Grid of customer logos that link to their respective websites/success case posts. The site owner should be able to add or remove these at ease.

Well I think the easiest way would to create a Custom Post Type called “Customer Logos”. After that you could handle content and images multiple ways:

More Precise Control but More Work

Create an image size which will represent each logo. Whenever registering your post type you’ll want to make sure that it supports thumbnail so that the Site Owner can upload a “Featured Image” which would be the Customer Logo. You could then create a Metabox to store your link which would be stored as postmeta. This will make sure that the user can only add a title, image, and link and when creating your grid you can make sure everything is consistent.

Easier but Less Control

Instead of the above, whenever you registering your post type you can just have it support title, editor of which the Site Owner can just upload the image to the post type and link it directly. The problem with this method is it gives the Site Owner more room to mess up any layout you decide to go with.

Finally

You’ll have to create a Post Type Archive to display your posts and some HTML / CSS to put them into a loop. Hopefully that gives you a better idea on where to start and what to do but you’ll have to do some coding.