Here's something i've been meaning to do - some modifications to the "hot tunnel" area that should help things out.  First, i ordered some .026 aluminum sheet, and a couple of extra baggage floor ribs.  You'll see why.  Next up is trimming the aluminum sheet so that it fits inside the tunnel, and it goes from the firewall to the spar carrythrough.  Then, I cut the flange off the baggage floor ribs to use as a support for the "false floor" that i just made.  I put the flange so that i could use the #30 holes as the attachment for the tunnel floor.  Then match drill the flanges to the inside of the tunnel.  I had to make it low so that i didn't cover up the nutplates that attach the cushion clamps for the brakelines.  The false floor ended up being just about 1/2" from the bottom skin.  then, to close out the false floor area i had to make a support piece for the aft edge.  The piece ended up being kind of "Z" shaped.  then i match drilled that to the fuse bottom skin.  After that, i just match drilled and dimpled the holes to attach the false floor panel to the ribs.  With all that prep work out of the way, I got into the Ceramic insulation paint that I got to insulate the floor and firewall and tunnel areas.  The paint is called Lizard Skin ceramic insulation paint, and it's supposed to be pretty cool.  We'll see.  you have to use a special paint gun to paint with it, because the paint is super thick.  It's REALLY light weight though.  it's kind of like automotive undercoating, but much lighter.  it's supposed to insulate, be fire retardant, and sound deadening.  So we masked off the floor area, and the tunnel area, and after a bit of testing, we painted a coat of the stuff.  It actually seems like it's going to do the trick.  After that, i cut a piece of mylar faced fiberglass heat insulation to go under the false floor.  After the paint dried, I set about riveting in the pilot / copilot floors, and the false floor ribs.  I didn't rivet in the false floor yet, because i want to figure out the fuel system mounting before i do that.  Sweet.