It's an easy job, disconnect the negative battery terminal, remove the speedo dash panel then disconnect the dials. At the back of these you should see alot of twist bulb holders, remove the one behind the clock, mine had a little picture of a clock on it, switch the bulbs over and put everything back together.
286 bulbs are what you want, you get them almost anywhere and in any colour, got mine from ebay.
good luck (Y)