Hi Momma, obviously not a UK model this one, but put simply a lamp has only two connections. Voltage in and neutral out as it were. Basically itdoes not matter which goes where as long as one is in and one is out, the bulb does not care. Its just the same as any other bulb. If you are at all worried contact me and I will do my best to checkup the service manual.
Whatever happens please remember you are messing around in a piece of equipment that runs at 4000volts and due to the design of its circuitry under certain fault conditions it remains lethal months after having been disconnected from the mains supply. its not rocket science as they say, but it is not for the layman either. Contact me via microwave-repairs.co.uk if you need further help.
patrick
March 2010