A:Answerit should. it is an single din radio.
most car radio are either single din, or double din.
double din is double the size of single din.
double din is like a media player radio, or large radio.
just looked up your xterra dash, it is a double din. this will fit, but you will have an extra hole under the radio.
to cover the hole you would need a radio instalation kit.
best buy should have it look it up.
A:Answeri am not sure what a 99 civic dash looks like, but i had an ex with a 2002 civic, and it was also single din, it should fit fine.
just looked up your dash, pictures attached, it will fit fine.
honda used a double din, so youll have extra space.
A:AnswerMore than likely yes of your radio is a single din, if it's a double din you need to buy the adapter plate to down size the hole. To avoid cutting your wiring harness you would need an adapter plug
