When you replace the timing belt the covers that hide the belt need to come off. Big deal? Well no, but the alternator needs to make room. That is also not a big deal... but attaching it again while holding the alternator up with one arm is a hassle.
Here is a trick that Schocki posted. Simple trick but very effective !!
Undo the bolts one by one and replace them temporarily with a long one. Then the alternator just slides over the bolts to make room so that the cover can be removed.
The bolts are: