As I was trying to put the alternator back in, the air duct that is bolted on the back lost one of its two fins which was cracked. I searched in the catalog and found that a new one costs almost $300.
I thus improvised a way to stick the fin back on in a way that would ensure it would stay on. Here are some pix of the result:
You can see the crack where the fin broke off:
other side:
inside:
I added some super glue in the crack for good measure.