Its not quite as simple as just changing a few bulbs Im afraid, they are all surface mound led's , and its a lot of soldering, swearing and risk of damage to circuit boards before its done.
This thread gives some of the details, in addition to the LED's you also probably want the gauge faces that are from Blackcatcustoms
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Blimey didn't know it was THAT involved! Looks good but I'll stick with the tango effect