I hate to sound disencouraging but I have looked into this very subject myself and I'm not that pleased with the facts - for the foreesable future plastic surgery is really difficult to get into for FMGs. This is especially true for the integrated route which is significantly shorter and highly popular with US grads. For this reason you will need at least 240 on the USMLE step 1 and a couple of very good references from physicians, preferably written by well known US based doctors; and research will not go amiss either. Remember that only 2% of places go to foreigners, many of whom might already be consultants in plastic surgery.
Considering how hard the intergrated approach is, you might have a better shot at applying first for a general surgery residency and then follow your surgical training up with a fellowship in plastics. This is a longer route and you will spend many hours learning operations that are completely unnecessary for a plastic surgeon. The vote is still out concerining which option produces the better plastic surgeon. Apparently, and dont quote me on this, forty percent of general surgeons who apply for a plastic fellowship are successful, and at this late stage of training the fact that you were originally a FMG is not important anymore, only that you prove yourself as a dedicated surgeon. However general surgery is getting more popular now unfortunately with US graduates, probably because of the 80hr working directive that was introduced very recently. So even this route is a problem these days for FMG. Having said that, I still maintain that your chances of getting into plastics are infinitely better with general surgery.