As I recall the hardest thing to do is keep the spring from pushing down on the upper control arm and causing you to not be able to un-bolt the bottom of the shock. What you want to do is weld-up a brace that will wedge between the unibody lip and the underside of the upper control arm. Now jack up the car and support the car on jack stands. Remove the front wheel so you can see what you are doing under there. Then, jack up the lower control arm which will compress the spring, and allow you to get at the bottom of the shock. Once the car starts to lift off of the stands wedge your hand made too in place and lower the jack that is holding the lower control arm up. The wedge you built will stop the spring from letting the upper control arm from returning too far. Now would be a good time to mark the shock tower as to which way is front so you can install the shock correctly the first time. Now, unbolt the tower and remove the shock and shock tower all at once. Now that the shock is on a bench you can remove the old and install the new one onto the tower. Now bolt the tower back in and then the lower end of the shock. Before you take the wedge out of place now would be a good time to install the strut rubbers. Unbolt the strut from frame or body end first then unbolt the lower control arm end. COUNT THE TURNS because this will effect caster. You will still need to have it aligned but you will be close enough to drive it.
I hope this helps