Not if it's 'fit for purpose' and saves him that big bill we all dread. I assume that it 'does work' Rich? Got any pics with the light on? 
I like your bright looking display. That was one thing that always bothered me, the display being too dim.
Here's the simplest way I know of to rectify that issue.
Forrester, Actually, I do look for work on the car. I get as much enjoyment working on the car as I do driving it, possibly more. It sure beats playing golf, and is probably cheaper too!
As for the illumination, I wasn't looking to increase the amount of light in the instrument cluster as in the link above, I just wanted illuminated needles. We have them in my wife's PT Cruiser and I like them. I did wire the LEDs into the lighting circuit using the two grey wires that lead to the illumination pod shown in the link though-very straightforward.
The illuminated needles are part of a bigger project. I am replacing my sun-damaged dash and cracked binnacle, and while I am at it I will be switching to a Mk2 console, fitting an EPAS shut-off switch and wiring in a solid-state heater control. It was rainy this past weekend and I was going stir crazy so I decided to do the needles. I'm glad that I did as it turned out to be a much more complex job than expected.
As requested here is a pic with the coolant light illuminated. This was taken in daylight and even then it lights up the entire instrument cluster. It's so bright I may even unhook the annoying buzzer as you can't miss seeing the light.
David and Adam, Did you buy the needle kit from the same E-bay seller that I did (chromemanics) or did they come with your guage faces? Just wondering if yours may have been better quality. The biggest issue with mine was the hole size for the spindles. Speedo was a touch too tight and needed reaming, the others were too big and required adhesive.