Hi if you take the top plastic cover off above the radiator which from memory is two plastic plunge clips that should give you a better view of it all, mark where each pulley touches the belt with tippex and do a drawing of each pulley and the way the belt travels either behind or over that particular pulley, good kit Dayco and INA are used as o.e., I wouldn't get involved with changing the alternator freewheel clutch in situ as they can be an absolute cow when the alternator is out of the car and on a bench these clutches normally fail way after the alternator and as most replacement alternators have a new clutch fitted its probably a fruitless and consuming exercise, only other tip is make sure you have the belt running true when you pull the tension pin out to release the spring tensioner as you will need Neanderthal strength to pull it back again if you get it wrong and remember to turn the engine over by hand a few turns to settle the ribs on the belt into their grooves, I have seen the new belts try and ride off of the crank pulley.
Steve.