Is there a way to make a CSS file be the last to load both with and without rokgziper active?

I ask because I would like to make an override file with my adjustments to various templates that use the gantry framework. I'd like to keep the overrides in a separate file, and I'd like to avoid messing with specificity for every selector if possible. If I just stick a new css link just before the closing head tag of the index.php file for the template, a few other css files are loaded after it.

If that is not possible due to other plugins loading their own CSS ect. (or perhaps gantry loads css from it's array in a specific order?), what is the best alternative for creating template overrides for the CSS?