Another upgrade. There's a big open hole that needs help. The platform-mate CRZ has a cover panel here. The gap is about 20" wide by 26 long.
I had a sheet of (abs?) plastic available from a crate label. Cut to size with snips, zip ties to attach.
Crossbar from a shelving unit - 1/2" square u-channel steel with slots all along it. Zip-tied in place using existing holes in the side panels.
Panel installed. Much better!
Back end is tucked under the existing panels. It only touches the frame crossbar, engine mount, my added crossbar, and the front cover panel. Nothing hot is within 2 inches of it.
Detail of front attachment point.
The front end is tucked in behind a 1" step up in the splash panel, which is behind the 1.5" front air dam. Minimal risk of catching air. I have 3 zip ties holding it in along the front edge and the rest is just tucked in place. It's solid.
I think the car is slightly quieter, but it may be placebo. I got a near-record trip this morning, which may or not be related.