By Justin Barrasso Saturday’s rematch at the ‘Rebellion’ pay-per-view is six months in the making. Josh Alexander wants Impact Wrestling to have an advantage possessed by no other company. His goal is to give Impact a world champion who will deliver every single time he steps foot in the ring, establishing a weekly product that fans of pro wrestling would be disappointed to miss. “Our wrestling is going to grow our brand,” says Alexander, who will wrestle Moose for the Impact world title in the main event of Saturday’s Rebellion pay-per-view. “The next step is for me to get that world champion…