I looked around and did a temp fix.
Went to style.css and added a text-align: center under ul.side_prd_list li.related_product {
Then went to pages/product/product.tpl and added <br> between the code to insert the related image and before the code to insert related product name
While doing this noticed that this section will also show the rating for the product. So I tested it and never figured out how to get the stars to center align, so I removed this line.
Not center aligning related products doesn't look good for my website. Maybe I changed the thumbnail sizes of products too small or something, but even with center alignment, there is a slight misalignment between the image and title / price. Seems like the center for the image is different than the center for the title and price so they look slightly off. Looks better than before, but not quite there.
Any thoughts would be appreciated.