I wonder what you used for rivets?
There's a kind of pain that I call "Puffy Paint", thanks to the wife. It's a really thick paint that comes in small bottles almost like PVC glue. It goes on thick like toothpaste and dries the same way. It's really a paint expressly made for writing on fabric and clothing, but works great for rivets. It takes a steady hand to get really consistent results. It's a shame I don't have a steady hand yet, but you can get such small little gobs of texture it works great for rivets.
To show you what I'm talking about, here's a link to the stuff at Michaels.com:
http://www.michaels.com/Scribbles%C2%AE-3-Dimensional-Paint-80%27s-Pop-6-Pack/gc1721,default,pd.html?start=4&cgid=products-generalcrafts-apparelcrafting-fabricpaintSo here's what I
don't know. When I did this tank, I installed the rivets with black paint, then base coated the whole thing black, then drybrushed it all white so the colors would show up better. That meant that I had to go back and repaint the rivets black before touching them with silver to give them that bolted on look. I'm wondering if I'd be better off painting the next tank completely, then using black puffy paint to install the rivets and touching with silver. That might save a step and some time, but I don't know how well the puffy paint will hold acrylic or hobby paint without the flat krylon basecoat.