i want to order a powerflex anti rollbar bush,but they are avaible in 3 sizes ,23,24,25mm,i have a 1995 3.0 euro m3,who knows the size i need?

It's listed in the parts catalog. Stock size is 22.5mm, so none of those are going to work. The stock bushing is better than urethane since it is firmer from preload with no pivoting friction. Flexing rubber does not add friction to the suspension like a sliding bushing does.

thanks, i will order a stock one