I ran 8.5" ET45 and they did need to come out towards the arch slightly, but by slightly I mean another 15mm or so, to make them sit level with the arch. So your fronts will be about perfect as an ET35
A 10.5" ET35 will have over 35mm poke than my old set-up. These might either poke out too far, or catch the arch, depending on how low you are.
I know people run 10.5" rears, and i've even seen people run 10" fronts with a pretty extreme offset, but 10" rears are my maximum choice, and that's what I run now.
A lot of what you are doing will depend on your suspension drop, if you have one.