Alternator has very low service life, in my experience about 500 hours. The last one worked for only 350 hrs. Seems that the brushes wore out after such a short time. Other people had similar experiences. Based on that I did not install the Ford alternator, I am going to return it. Instead I bought a Hartsell Alternator, AL 24-F60. Installation required to shorten a spacer to fit into bracket on airplane. Luckily I had access to a lathe where I was able to shave off about 2 mm from the spacer. Otherwise the installation kit was ok. The alternator is metric, probably comes from a Japanese car. The alternator on my 2001 Toyota Camry has so far lasted for more than 5000 hours with no trouble, hope for a similar service life on my airplane.