the coilovers have two metal rings on them mate an adjustment ring ( the top one ) and a locking ring ( the bottom one) the tool is a c-spanner, jack the car up and try and lossen the bottom locking nut off first, this could be easy or they wont move at all depending on how old the coilies are and how they have been looked after ! It may need a hammer and bolster in order to free the locking nut or some heat, once you have got them free you can wind them up but a few mm either side until your happy, you may need to wind the gearbox side one up a little more as that side always seems to sit low