Question for Jews about temple-era Passover

[Athetotheist]

I've been trying to get my head around the pre-rabbinical observance of Passover, but I can't get a clear picture of it. My understanding is that a Jewish day begins at sunset, but the use of the maddeningly ambiguous term "evening" in every description I've found has me hopelessly befuddled. To my Gentile mind, evening goes from before sunset through twilight to nightfall, so that term doesn't help me here (it's like trying to figure out the old Vaudeville joke----"If ten pennies make a dime and ten dimes make a dollar, how much is a bunch of nickels?").

I'm trying to get the gist of all the components in order (the Preparation, the slaying of the lamb, the days of unleavened bread etc.). If I'm correct in understanding that sunset begins the Jewish day, can someone give me a clear, concise chronology of what happened in the temple-period observance of the Passover/Unleavened Bread feast(s), using sunsets to specify exactly what happened on each day, and which day of the month (the 14th, the 15th etc.) each day was?