Without seeing the vehicle, it's impossible to say where the leak is. But, just because you can see it dripping in one place, doesn't mean to say that's where the leak is. Coolant can leak from one area, then run down the engine to drip off in another area. Squeezing on a coolant componenent will cause the leak to show itself but nothing more. The coolant system needs pressure testing at a garage qualified to test cooling systems to identify and cure the cause of the leak
I can hear a little air in there sometimes, but the box on wheels is running great again.
I can see myself modifying the firewall in the future. Seems like a terrible design flaw to have such a vital component stuck in a place that makes what should be an easy fix an impossible fix anywhere else by your driveway.