Grid view in Marketpress without using the Framemarket theme?

Hello and good morning. I was wondering if anyone knew of a way to get a grid display of products without using the Framemarket theme in Marketpress. I am using a theme that works well for this site and would really like to stick with it. Tried using a third party multiple themes plugin...that almost worked but because I was only using it on the product pages I couldn't customize the grid. Thank you for looking.