One of the things that really needed attention on my 550 was the tach: the face was cracked and faded, and it looked pretty beat up. I kept looking for reproduction gauge decals, but all the ones I found were goofy-looking "Cafe"-style, or really didn't look stock enough for me. So I got a screen printing kit and did it all myself. The green and red are color-matched spray paint, and the white is Jacquard screen printing ink. It was way too much work to consider doing again, but it sure looks sharp.
And, well, while I was in there, the guts of the tach were aging, and they weren't exactly accurate in 1975 when it was made, either. Plus, with all the time and money I have into my motor rebuild, I want to know something besides "Oil pressure" or "No oil pressure". So I figured I'd replace it with a more modern design and add some sensors. It's a custom printed circuit board of my own design, built around an ST ARM Cortex-M3 microcontroller and a snazzy OLED display. The needle is driven by the stepper motor from a Ford Mustang. It also measures oil pressure and cylinder head temperature. The oil pressure comes from a VDO 360009 gauge, and the CHT comes from a Westberg thermocouple which sits under the #3 spark plug.
I mean, why not? If you're going to do something, you might as well go all-out. No sense half-assing it.
If others are interested in doing something like this, I'd consider putting kits together. It wouldn't be cheap, but you could have the only CB on the block with an electronic tach.