The WP on this car is not that bad to do. ALL the bolts are accessible, with a bit of prep ad the right tools. Though ps2cho did his without removing the PS pump I highly recommend onbolting it and pulling it to the side. You may NEED to do this anyway if you're replacing the tensioner. I believe the PS pump and the tensioner share a bracket.
TAKE PICTURES as you disassemble! It will likely benefit you greatly if you're unfamiliar.
You'll need to remove the fan and pulley. It will give clear access to the front area of the pump. There are two small ribs on the timing cover behind the pulley. You should be able to see them clearly, place a rod (1/4"?) with the last inch bent to almost an "L" between the ribs. Turn the pulley until a corresponding hole appears and slide the bent end of the rod into it. This will lock the pulley in place to facilitate removing the pulley bolts.
The WP bolts that are hidden can usually be easily gotten to with a long extension and a swivel joint. A swivel SOCKET of the proper size is best. Though it may work, using just a swivel joint with a socket on it can get clumsy and reduces the already tight working space. As mentioned by another poster, a 1/4" extension may work better in the narrow spaces between the intake pipes. The WP bolts are not torqued that tight, don't over-tighten them. I replaced mine with stainless hex head bolts.
There is a DIY tutorial on the tensioner here somewhere that is excellent and I would say ESSENTIAL. Read it and re-read it. Not only will it guide your set up and installation, but it will provide a good understanding of it's proper function and adjustment.

Hope some of this helps.