[Steven Zahm]

@ George

re: I would like to show all these on a single page, not separate pages. Will two or more separate category override files work for a single page, all at the same time?

Then all you need are the card-single.php and card.php template override files.

You would check to see what category the current entry is in and then change the layout as you need.

Something to consider as an alternative. All entries are CSS classed with their category slugs, so, you could use CSS to change the appearance that way too.

Hope that helps!