Rear to adjustment buch stuck

[Hobz]

Hi

I`ve just tried to have my wheels all alligned but the guy in the garage said he couldn`t do one of the rears as the bush used to make the adjustment has siezed. he said I need to replace the whole arm as the bush isn`t supplied on its own.

I`ve had a look myself and the cam bolt dosn`t rotate as it should instead when you try to turn it the whole bush tries to rotate, which it can`t cos it fixed to the arm.

The new arm is £30 but in order to fit it I`ll have to remove the cam bolt which I can`t cos it`s siezed! I`ve seen elsewhere that people have had to angle grind the bolt off :( don`t fancy trying that although I do have a small grinder.

I`ve tried penetrating oil to free up the bolt but no luck so far.

Any ideas how to free the bolt to allow adjustment?

or

How to easily remove the bolt / arm to allow a replacement?

PS its a 04 Reg Mondeo 2.0 TDi if that helps.