Mixing colors helpp

okay so my hairs is cut really short, a boy cut. But it's been through a lot and is currently a mix of blondes. It was  black before i went blonde and red before the black. so my hair still has an orange/pink tone at the ends. hair dye usually covers it but it comes back after a few washes. Right now the first inch of my hair is a nice light ash blonde but then the mess of orange and pink tones starts to show.
now I have 8.1 (ash blonde) dye but i think that might look too dark. so i also found a 9 1/2-1. (platinum) i'm thinking of mixing them. With a bit of 0.22 (anti orange blue) to get rid of the orange tones. All the dye is igora. i also have 30V and 20V peroxide. Any tips or opinions?