Beautiful car. The "cracked hose" looks like the drain snout for the under-dash climate box. it has a flexible lip that is supposed to open to let water out, but close to keep engine fumes from flowing back. My 82 Dodge Aries had a very similar looking drain (same supplier?). I was getting water on the floor and found the "lips" stuck together. When I popped them open, a bunch of water flowed out. Not a problem in my 300D's because that drain is cracked just like yours. I don't smell engine fumes, so no concern.

If the wiring diagrams didn't explain it, ask and I'll take the time to post photos of my pressure switch, but could be different since CA models had a different air filter over that (since removed).