Coolant leak under dash

this is a little off subject here, but why does everyone get rid of heat when they bd a mazda? i kept my stock heat with a 8 inch bd.

I would've kept my heat, but when I was modifying the box my core was in, I accidentally cut into the core itself. I was trying to get it back together for a show, so I just left the core out of it. I am gonna replace it soon.