Replying to Breaks wide enough ?

Hi.
I have the Invaders at the moment. I am thinking about getting anthems or elizabeths to ski the whole mountain.

If i choose the anthems, can i make my 90mm marker griffon breaks to fit on the 93mm wide anthems?
Is it possible to wide them that much. i think i will let a skishop do that.

And wich size should i choose on anthems? I am 173cm. should i take 178 to ski a bit powder and get speed without loosing the fast spinning skills. or should i take 171cm if i mainly do freestyle?

Thanks for help!