RIKFrey here - yeah a few details to cover I guess..
After cutting the hole in the hood I had to (carefully) cut out both lower braces. Take out about a 2" section weld the hood braces back together and them reweld the braces back to the hood in the new location. It was 1/2 a day in metal work. the other 1/2 day was spend fabricating the trim ring from flat steel using a stretcher/shrinker. I have a few more hour in the hood as many of the underside vent holes were sealed up -and I took time to wet sand it donw to 300 grit.
As for the cowl being sealed up - I loose the lower vent air into the car. But I either run with the (power) windows down or the AC turned on and the windows up. I've had a little fogging on the front window, but just running recirculated air clears that up. But I[ve only see that once or twice ona cold morning when I first get out onthe road.
One question not frequently asked is air intake. I'm running a 408W, 1200 CFI throttle body, AFR205 heads, headers, 3" exhaust, fuel injection. 464 RWHP and 422 TQ the dyno looks like 45 degree line from 0-6000 RPM. We dyno'd the car with the shaker on and shaker off - dyno numbers were the same.
I'm just a hobbiest - so doing this work is mostly time and some metal fab skills. The average dude could tackle this project, ut I have to admit. I DO turn a few heads going down the hi-way...
Oh and BTW thx for posting the pic's I can always be reached at RIKFrey@Comcast.net
(Located in Beaverton, OR USA)