Hi can some help me im quite new to hairdressing nearly completed my level 3 at college. my friend currently has 5/66 wella colour touch on hair she has alot of bulid up years of colouring! she wants to go to 6/3 . Can I achieve this! eraser colour remover the going in with 6/1 if hair is quite golden when colour removed? any ideas please!! maybe should i test a piece of hair first?