Also, for cosmetics, you can get the Tsuru front grill and lights. Here is a link to a pic of the modification... Tsuru front . I think you can order them from Mossy Nissan in Cali. I read the '99 Tsuru has projectors.
Check out http://www.dg-racing.com/ for their alternative bodykit. $20 or so for the front skirt isn't too bad. I've got one on my car and it seemed to help with stability at higher speeds. It's flexible so you don't have to worry about cracking a body kit and at high speeds the skirt flexes and directs the air under the engine stuff for better air flow. I purchased the 4" skirt but I'm pretty sure the larger one will help more with aerodynamics. I'm wanting to find the fronts to some of those racing sentras that comes down low and is made of thin, lightweight plastic or similar type of material.