I installed the Stock Air Box back on our 2017 trike today. I also re-installed the (EBS) catch can set up I had previously used. I decided to re-rout it out of the air box and re-rout it under the frame.
I think it turned out well. I had to make a clamp and mount it to the existing exhaust clamp (see pic hose running through clamp).
I had to drill a small hole in the stock air boxs bottom for the hose to exit and rout the path of the hose not to touch anything and not to get melted.
Ride Safe All,
Bill G