Hey mate.
sorry Mot to get back last night i got called out

i use boot polish. and in well happy now.
mine had gone all grew but now the are really black!
normal black boot polish. use a brush to put it on then leave it to set.
once dry its all in the buffing. you will be happy. and it lasts!
i just kept re applying until i was happy!
i think it would be easier than painting
