Do I have to dismantle all the central dash to change bulbs.
Thats what I had to do on my J63D, for the exact same reason.
Advice:
Turn the handles fully to the one side, - it will make reassembling
easier to get right first time.
After my first reassembly, everything looked SO great and I was happy - until I wanted to turn on the heat, and found that the "max-heat" was now "12 oclock" and not "4pm" ! - argh! :-)
There is a (german) description of the procedure here:
http://www.espace-freunde.de/modelle/j63/anleitung/anleitung-index.html