10" might be possible in the rear, but again, you seriously have to ask 'why'.
with the appropriate offset, it could be do-able, but if you can't find exact details, then you'd want a wheel store that is prepared to change them for you if they don't fit.
i still think 10" would be really pushing it.
i have 8.5 x 19" wheels on my GT, front and rear. they fit without any probs and without modification. offset is +35mm. tyres 225/35.
