98-02 saab 9-3,is it possible to buy specific mesh for saab or can stainless steel mesh about 3mm thick be improvised

The grille(s) is/are held in by plastic clips that are part of the piece itself. It can pop out fairly easily. But if you want to replace the whole grille unit with mesh that is not specifically for a Saab grille, you will probably have to rig something up on your own. Your question is very vague and it would help if you supplied more information like the model and year as well as a bit more detail about what you plan to use as a replacement grille.

l was sort of thinking about this on my 9-5 but decided it would look a little tacky as the rest of it is 100% stock. It may look more appropriate on a 9-3 though. If l were going to do it & use my existing grill l would remove the grill & then cut out all the black plastic pieces that run up & down & across. Then l would use some sort of adhesive or clips to mount the mesh behind the chrome grille. Of course if you're feeling extra rich u could save a lot of hassle & buy this:
http://elkparts.com/product_info.php/cPath/74_767_780/products_id/1054

l am sure if u googled ''Saab mesh grill'' you'd get lots of helpful info or images. Good luck!