Mystery Alternator component

[Camarade]

Hi all,
Took alternator housing off for a re-paint. Had to remove the bobbin to release the casing. All good except that I found a small cylinder that dropped out from Lord knows where and was wondering if anyone knows what it is/where it belongs.

[Gnasher]

Looks like a location dowel from the cover.  It should be in the front lower bolt hole. 

[Camarade]

Wow....didn't even know that such a thing existed. Well it certainly fits where you say, so looks promising. Will post again once I get the cover back from the spray shop and offered it up. Thanks!