If the holes are pre drilled then no, but if it's a plain ski, then you could, but I think it's only a matter of a cm or two. I'm no expert though, so I'd go with what the fitter says.
Your boots sound great. When you go to have them fitted don't turn up in a thin pair of cotton socks! Warm woolen ones are a lot thicker!!
yah for the boots - with your own boots you really don't care about hire skis - well at least I don't mind that I've poved out and have hire skis
bushmanpat is right - wear the type of socks that you're planning on wearing with the boots on the slope when you get them fitted. I used to walk around the house in my boots all the time to "fit" them properly - my calves are now too big and I can't wear them any more ($1,000 worth of custom made boot when I was 19)
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