I sent an email to Bill at Airflow about the hardware for attaching the butterfly valve extension on the plenum. He was a little surprised at the question and we had a chat about it and he suggested rivets. Well I decided to use #8 screws because as I brought to his attention that you cannot get the long cooler attach bolts on because the butterfly valve hinders the center attachment bolt from being able to be inserted as it blocks the center hole. So I checked and there was room for nutplates so I went with that to attach the two parts.
I drilled the nutplates and riveted them in place and used my supply of #8 stainless screws to attach the parts.
I also did some profile work on the rear angle that mounts on the firewall and the mating area of the side supports and the front support angle. Now they are ready to prep and paint.
