I put two on the brace that goes from the tipup rollbar to the rear bulkhead.
I put one in the mapbox and two under the panel on the panel support ribs pointing down.
These are nice lights but the light seems to go mostly straight down. not much of a flood. They are not super bright but that is good because at night they make a nice ultra white glow in the area they are lighting.
I put one of these just behind the roll bar brace to the rear bulkhead. It is working really great as you can change its direction/position. I use it both for night flying in place of a flash light or reposition it for the luggage compartment.
I bought some red LED assemblies (like the ones in the picture in the original post on this thread) from www.allelectronics.com. They cost $ 6.00 each... Then, with a dremel tool, I cut away the "dome" part of the LEDs, and now the light is diffuse enough to illunminate the entire panel.
They also sell led strips which are great for the panel if you mount them under the glareshield.