It's happened to me before. I (slightly) over filled my 2000.
Blew oil all over.

I changed my oil last Thursday (Amsoil - sorry had to)
But I put 3 qts in, and it's showing full. So the myth that
Softails hold 3.5 in the tank alone is just that. Maybe 3.5 total, including the lines, filter ,crankcase and etc. But don't just drain it and dump 3.5 in there.
Last oil change, I put 3 in, rode around and it was a bit low.
I added aprox 1/4 qt to bring it to the full line
(Checked warm after riding)