The new keypad has built-in illumination, via LEDs. So, the existing little incandescent bulbs on the CLS circuit board need to be removed. Some of mine were burned out and I had just located a source for these on the web, but now it looks like I don't need them.
BTW: There is a single Red LED for the "HOLD" button. Don't take that one out. There is an opening on the new keypad that lets this red LED shine through.
The ribbon leading to the connector on the new keypad is marked with a black strip on one side. But it is still ambiguous, as the plug will fit in either way. I opened up another controller that has the upgraded keypad to see what-was-what. Wouldn't you know, that other controller has the black strip on the OTHER SIDE of the ribbon connector. So, in one case the black strip is on the low side and on the other it is on the high side.
Pin 1 is marked on the CLS controller circuit board. And I have indicated which end of the ribbon goes to Pin 1 on the controller board.
You may see that there is an extra green wire. That is to power the red LEDs under the illuminated keys.
It connects to the digital display power supply, NOT the power supply for the little incandescent lamps that were removed.
Specifically the wire needs to connect to "Q1" pin labeled "e". There is a trace that leads from pin "e" to a little hole in the PC board. This is indicated in the picture with a red circle. This is where I connected the green wire.
The new ribbon connector needs to be folded back on itself pretty tightly for everything to fit back in the controller.
Here it is with the new keypad. Boy is this nice! No more pressing the buttons two or three times to make changes !
The other nice thing is that the keys are illuminated now with relatively 'safe' red light. With the old keypad, the incandescent lamps were 'white' and not filtered in any way. So, I kept them turned way down to the point where they were pretty useless.
Sure, a brand-new keypad like this is going to not be easy to come by, however, busted controllers with working push-button pads can be found. In fact I do have a busted CLS TRANSLATOR controller I got for cheap. (the one with more buttons than the one in the pictures here) It has a working push-button keypad, but the panel is longer, so it won't fit on this standard CLS controller.