In preparation for installing the avionics I transferred the instrument panel template onto the instrument panel and began fabrication of a shelf that runs between the instrument panel and the firewall to mount the various components of the avionics.
First, I updrilled all of the rivet holes connecting the instrument panel to the center console and the canopy sidewalls. Next, I clamped the aluminum instrument panel provided by Zenith to the installed instrument panel to check for fit and to transfer the panel openings to the panel.
The bulk of my time was spent measuring and fabricating an avionics shelf. To accomplish this, I added two heavy-duty (0.04") aluminum angles that connect the firewall to the instrument panel. Their placement was a compromise between maximizing the width of the shelf and maximizing access to the floor area on either side of the shelf. I ended up with a 435mm wide shelf (490mm in depth) with 275mm on either side for access below the shelf.
With the size established, I drilled out the ends of the angles and attached them with clecoes. Next, I cut out a rectangle of 0.034" 6016 sheet aluminum to fit inside the angles on the side, the firewall in the front, and the instrument panel in the back. With some additional trimming and filing, I got the fit exactly like I wanted it.
Aluminum instrument panel template clamped to instrument panel for tracing.
The two new angles attached outboard of the two angles that support the center console.