Hi mate - I dyed a faded black pad set back to black
the pad set on one side had turn faded brown
the print was white writing
i only dyed the covers not the pads
I used dylon mp dyes - one tin - boiling water in a plastic tub/washing up bowl, that would hold hot water
I left it for about half an hour to soak with a stir once in a while
The print turn grey straight away and soaked the colour up - the brown turned back to black and a solid black
I didn't mind them turning grey as they matched the grips
you can turn pad sets back to the right colour BUT it will turn print colours around and may not be what you are looking for - then it will have to be a repro set
you can try it and see if it works - nothing to loose unless it's too valuable to change
hope this helps - cheers B