Yup. I used a pair of mole grips on mine when I realised I didn't have the m10 spline bit. All came out really easy. I then also purchased an M10 spline socket too as it gets used for seat belts etc. worth having.
Do you happen to know the sizes that get used in a T5?
Having read this and other similar threads I'm looking to get a set, but don't know what range to go for. There are some cheap-ish sets that have M5, 6, 7, 10 and 12 splines. Is that a big enough range?