The belt can be too tight, this can also cause it to squeal, also look closely at the alignment of the power steering belt just a bit off and you get the squeal
as far as the turning radius, what size wheel and tire are you running the larger the wheel and tire the wider the turnig radius, remember the gto is a wide track car i suggest get with another gto owner and see if your radius is wider.
as far as the third ?? no idea
Mike