How would you guys go about it if you had two different characters with the same first and last name? It's kind of tough because the two characters speak to each other face to face so it seems more challenging to me than it probably is.

The way it stands for me so far is that I refer to one in action and dialogue by the first name and the other by their last name.

You guys think this'll work?

You could refer to one by his full first name and the other by the shorter version, like Mike Smith and Michael Smith.  In dialog, everyone can still refer to them as 'Mike.'


Phil

I used an alternate spelling once when I had Poe (the real character) and Pough (his alter ego).

Getting back to what I said before...  I was named after my father.  Growing up, he was Phil and I was Philip.  There was never any confusion at a family gathering when someone called out 'Phil.'    I never even answered to that name until after my father passed away, when I was in my twenties.  My family still calls me Philip.


Phil

I had this problem a long time ago when I wrote a feature.

I use the # symbol.

The reason was it wasn't father & son, friends or stranger, it was the same character split on screen using a diversity of time sharing the same space but not quite in an interactive environment.  A David Lynchian effort of mine.

Looking back, I can see that would be annoying but both characters would still be addressed by their christian names, so not sure of a better way to improve on that.