Simple Theme - Change First Image Selected after Product Page Load with variations

[razoredgeknives]

Hi guys. I have a product page where I have multiple variations. the first image that loads always defaults on the variation that's selected, however, I want it to default on a specific image until the customer clicks the options. 

I found some articles here that explained how to do it in a different theme by editing the openproduct-media-gallery.liquid file but that file isn't present in the simple theme. 

Any help is much appreciated!