Guys i had a look for the condensor that supafatto showed me couldnt see it anywhere.Theres a little black box about inch squared next to the coil would that be it.

The Ballast Resistor normally needs no changing. They usually last decades. But certainly if your is defective, or trying to make the car look new you can replace it.

They are very easy to test, just measure the ohms with an ohmmeter. If it's in spec, there is no technical reason to change it. The ohm spec is here click it: Coil.

The condensor is not changed with the coil. It is changed with the points every 12 months or 15000 km (points & condensor are a set) -- see Schedule.