Hey there chap,
There have been a few threads on here on how to do it, as i had a pair of DC Nippons that i stripped & had repainted. One of the way's is by using a Sharpie paint pen, i needed yellow & could only get this colour from the States
Basically i painted in the lettering(really need the fine point marker), i ordered the medium
. The paint went outside the lettering & i decided to let it dry(i painted the lettering 3 times in total), i then used a little flexy rubbing block with 800 wet & dry paper(rubbed wet) very gently till all the excess paint had disappeared. Then i popped along to Halfords to buy some ultra fine rubbing compound to bring the paint back to a nice glossy finish.............here's the end result
Hope this has been of help to ya fella
Buz