Rough opening.
Cabin Filter test fitted through the new slot. The left corner of the cabin filter hangs out of the firewall. A new molded door will cover the filter on the finished product.
Shot of the cabin filter through the cowling vents.
Shot of the cabin filter into the cowling. Looks pretty good to me so far.
The next step is to fabricate the filter base, filter duct and a firewall cover. Not sure which material I will be using for the base and duct. It might be fiberglass or sheet metal. Overall I think I am satisfied with the fit and will continue on this path. I will make updates to the thread when I make progress.