cleaning up a faded black cab

[glenbat]

i got a feeling my cabs had a re-spray at some point and the colour has started to fade a little, from a distance she'll look clean but up close een after a good wash she looks a little dull if that makes sense, any ideas on 'blackening' her up a little?
Not too sure if a wax would help? Or will i need a t-cut type polish with a colour additive in it something like colourfast?

[tommype30cab]

farecla g3 rubbing compound and some cloth and a bit of rubbing matey.