That is very similar to what I have been running in my Westy for a few months now, but, I have a couple of issues that I'm still trying work out before I put the info out.

But, if you do decide to try this, I would suggest that you go with the "horizontal" mounting of the resistor instead of the "vertical" orientation so the resistor doesn't touch the formed plastic sheet that covers the instrument cluster.  This causes the light to flicker on and off with vehicle movement.  Also, the resister that is pictured looks to be of the same wattage rating that I had tried first and found to get warm enough to eventually melt a hole through the formed plastic sheet.

I'm also experimenting with a few different LEDs and mounting depths to get the light pattern to cover the entire instrument face.  When I mounted mine as the one shown on the web site, the light was concentrated in spot that only covered about the top 2/3 of the face making it impossible to read the odometer numbers.

I just purchased a digital camera and will now be able to get some photos ready for a future posting.

I'm sorry that it has taken me so long to finish this project and write-up but my Vanagon has had higher priority problems and I've been distracted by them.  I put a new motor in it this past weekend, so, I'm hoping that I'll be able to get back to the LED project soon.