Can anybody tell me where to get this setup?

It is tempting to run ducts to the cowl since the area at the base of the windshield is a high pressure area. I tried this 45 years ago on my 68 Roadrunner after reading a magzine article. What I didn't think about was the cabin air conditioner/heater also draws air from the cowl. Came out the next day and gasoline vapors were on the inside of the windshield.

So if you take air from the cowl, you have to completely block off the vents to the a/c heater.

If you ever come across a 68 RR with two covered holes on the firewall, let me know. I might want to buy it back.