We were registered Democrats our entire lives, until Trump became President. We quickly learned that we were on the wrong side of life (although we consider ourselves moderate conservative, we are pro-choice and are not hardcore religious...but that's a subject for another day). We instantly became Trump fans...and we're Mexican/American! I was informed that if we're independent, we can't vote for a Republican Presidential nominee. So, do we have to register as Republicans in order to vote for Trump?
Edit: Forgot to add we are in California!
Doesn't matter, you can vote for whoever you want. My fiancee was actually just asking me this last night. She said she was afraid to register republican because it's public record, her employers could find out, etc (imagine, we live in a world/country where we have to be afraid of people finding out who we voted for or party affiliation) so I told her to register independent, libertarian, or even democrat. In our state, you can even vote in whatever primary you want regardless what you're registered as (this varies by state, though), so here it really doesn't matter (especially since you can register, or change party, as late as election day). She genuinely thought you could only vote for whoever you're registered as, and my response was basically "if that were the case, we wouldn't even hold elections, we'd just give your vote to the party candidate you're registered for."
tl;dr -- vote for whoever you want in the general election, regardless of your party registration