Water in the cab

[alborz]

I have a peterbilt 387. I have noticed when A/C is running or it rains I see a small amount of water running from behind the glove box to passenger footrest. Also when it’s raining I notice water from under the gauges assembly dripping to driver foot area. It gets the wires around and behind the steering column wet. This happens when actually I’m driving in the rain. I have checked the firewall from engine compartment no openings found. Also the A/C drain tube is ok and unclugged. The A/C and heat system assembly is connected to the firewall just below the windshield outside the cab with few bolts and nuts. How water gets in is a puzzle. [/size][/b]