Now that the Kanthal is coiled and the glass is cut, I was able to assemble the heater core. I had some 4.5"x9" firebrick left over from a previous project, so that's what I used. I used 3 bricks. One brick acted as the support base and power pass-through and the other 2 bricks were used to clamshell around the quartz tube and heater wire.  I used some aluminum L-bars, hose clamps and bar stocks to complete assembly. Note that the wire coil is only around the center 3". I finished it off with some aluminum framing extrusion. I wired the ground onto the frame and attached the white/black AC power to the steel bolts.

Caution - when working with firebrick - you should soak the bricks in water to prevent any dust while cutting.