Start from the back and work toward the front.  First install the big main
unit.  Then, slide the first tunnel into the front of it, be careful with the
sealing trim.  Then, 2 screws through the holes in the front of the tunnel into
the roll cage in the ceiling secures the tunnel.  The 2 screws are easily
accessed due to the shape of the tunnel.  You should use a metal plate or big
washers with the screws to strengthen and support the tunnel. The second tunnel is
installed the same way.  The smaller tapered tunnel is supported by the
second tunnel and the front unit -- slide it into the second tunnel, slide the
front unit onto that, and raise the whole thing up and screw into place.

I installed a '90 A/C system into my '85, and had to add the brackets on the
sides of the main unit and drill holes for the tunnel screws in the ceiling.
Also had to drill for the screws in the front unit.  It wasn't that easy to do
it alone, but I did it and it works well.  It will help you to have an
assistant to hold things up while you are working on them.

(PS: If you ever have to take off the main unit, the first tunnel will come
down and you may have to do the whole thing over again.  Make sure the A/C
works before you put any of the tunnels on.)

Any questions, float me an e-mail

Bill Marshall
85 GL Tiico "Pandora's Box"
Aurora, IL