I wiped down the area on the firewall where the heater valve will reside with enamel cleaner. I applied a silicone sealant that came with the heater valve to the heater valve, I bolted the valve to the firewall with stainless steel screws.
I taped and papered up the left edge of the instrument panel in order to prime and paint the modified edge of the panel. The edge was primed and painted. I used a file and the die grinder to put a chamfer on the three sides of the aft top skin, so that the skin will transition more smoothly to the underlying skins.
