Forward Tunnel Cover Mod

Here's a quick update on a common mod that it seems a lot of builders do.  The forward tunnel cover is a fairly long piece at around 4' or so.  There may be times you just want to have a peak down the middle section without removing any interior panels and what not that you've installed.  In my case I'm installing the Aerosport Quad Armrest, which will hide any split in the tunnel cover, as well as the full Instrument panel and center section making tunnel cover removal a bit tedious.  I also need the cover to accommodate a larger hole for the fuel valve stem.  My engine pick up date has been pushed back to the second week of December so decided to tackle this small modification.

I started with using the drill press to enlarge the fuel valve hole to 1" to accommodate the valve stem. Then I drew a line centered on the hole to designate a cut line.  You'll want to install some connecting pieces that you'll secure with rivets to the forward piece and use nut plates on the second piece to allow the split cover piece to re-secure.  This prevents lateral movement of the tunnel covers and in essence makes one big giant tunnel cover from front to back.  I used the same hardware listed out in the plans for these.

Now in my typical overthinking fashion I fabricated two nut plate bases and did the match drilling before splitting the cover. My thought was that would ensure it would come back together correctly once I install it.  However that wasn't the case and I had to drill out the rivets and try again.  On the second attempt I used a single piece, match drilled the 1" hole and then opened it up on one side to accommodate slipping it onto the fuel stem.  I used a angle grinder and split the pieces, riveted on the nut plate base and then temporarily fastened both pieces in the plane.  Then I did the nut plate hole match drilling.  Once I cleaned up the holes and dimpled them I test fitted again and it all lined up perfectly.  Then it was just a matter of riveting on two nut plates and it was done....

Well that really wasn't all that was involved.  One item that popped up while I was working through this was how to accommodate my new AC Freon lines with the tunnel cover.  I stared at this a bit and quickly realized I needed to make a few holes for these lines to pass through.  Then I had to make the decision if in order to remove the tunnel cover do I want to disconnect the actually lines from the fittings.  This would cause Freon to go all over the place, not a great idea.  The only solution is to make a slit from the hole to the forward of the piece to allow the lines to slide though when attaching it.  I used some rubber gasket material I have to finish the cut out and edges and give it a clean look.

Here are some pictures-