But make sure you do it up super tight again as you end up with the problem I have. A worn crank shaft, key way worn in the alternator pulley and the back of the pully smashed and the timing going slightly out. I had that problem after 200 from buying it from a chap. Going down the motorway made it worse and noticeable.
The obly way I have been told you can do it up is to have a 6ft bar underneath the car and but all your weight onto it to tighten it up as it has to be done up to more torque than the landy engine. So I was told anyway.