Factory, 77-on. Showing two different types of switch, and damage to a third caused by heat from the bulb (Phil Townsend). Although the position of the bulb indicates that the damage is more likely to have come from the design on the left, and perhaps the middle switch is a redesign to overcome the problem, Phil reports that both types suffered damage, and he fitted LED replacements as here. However the design of the 'bulb' means that it doesn't make proper connection to the spring, as there is a hole in the spring, and instead of a largish blob of solder on the end of a typical incandescent bulb the LEDs centre contact is much smaller which doesn't make contact with the sides of the hole. In Phil's case these switches are illuminated with the parking lights, not to indicates that a switch has been operated. But Mike Carter with a 1980 LE says his only illuminate when they are turned on, not with the parking lights! The factory wiring diagrams clearly show night-time illumination wiring (white/red and black) going to all switches and the heater controls. I can imagine a shutter behind the rocker allowing more light to come out with the rocker down i.e. switched on than up, but I can't imagine being able to see it at all in daylight.
Cut at the copper strips, three elements minimum
Connector block ...
... but heat-shrink is just as effective and less obtrusive
1/8" gap on my roadster ...
... the V8 has beading in this gap, but it can be lifted out of the way.
Almost invisible when driving
Way too bright at a full 12v
Brightness reduced with a resistor. The reflection from the dash panel and tops of the fresh-air vents looks like it might be distracting compared to the illumination of the switches and controls, but in practice it isn't.