mATT84DC
That's tricky. Firstly, you will only get PPL privileges when you do the conversion. There's an extra step required to get the IR done.
Secondly, your FAA cert will say something to the effect that it is only valid when accompanied by your original cert, and any restrictions on that original cert will apply. If you wouldn't be legal to fly a 172 at night in your home country, you *may* not be legal to do it here. I'd email the FSDO you intend to go to, and find out just to be sure.