"So, anyone named Cohen is a Kohain?"
No, but it is an indication. Lots of German Jews changed their name to Cohen (or some similiar iteration) to avoid the German draft. (Priest were exempt.) You have to prove genelogy and that various events did not occur (e.g., grandma was not a convert, etc).
"Do all the historical restrictions and rights apply to all descendants of Aaron, or just the firstborn?"
Depends on what one means by "all the historical restrictions" as that varies by whom you talk to, but not marrying a divorcee, not marrying a convert, various restrictions related to being in a room with a dead body, etc. still apply.
Not sure about the firstborn thing, as I am the firstborn, and never asked about it! I don't think so.
"So are you what they call a Messianic Jew?"
Yeah, I guess so.
"Do you affiliate with any Christian denomination?"
Anglican, mainly because my local church has about 10 other Jewish coverts, although I have also attended a so-called Bible Church. The traditional Anglican service (Paschel, et al) are also reasonably similar in format to what I know, which was comforting to a convert. This particular local church is also very serious and biblically based, neither adding, nor subtracting.
Well, Mean West Texan, you're an interesting person. Thanks for the info. I'm always interested in learning about the history and beliefs of others. And, since I'm currently teaching the Old Testament on Sundays -- we just did the Babylonian conquest in 600 bc -- I'm particularly interested in Jewish history and tradition.
If you were an observant Mormon, according to our scripture, as a literal descendant of Aaron you might have some kind of claim to the office of bishop, but I'm not sure how that works. I've never seen it.
BYU has a study abroad center in Jerusalem. One of my daughters and several nieces and nephews have spent time there. My daughter came home with a real feeling of kinship and respect for the Jewish people -- and a fear of the Arabs -- at least the ones in Jerusalem.