Just save up your money and get some long tube. haha Why spend the money for the short header and not gain anything or very little. I would just wait and get some long tube. I am not sure what you need to buy if you want shorties but I would just save for long tube.
1999 Silverado 1500 Ext. cab Red 2/4 hotchkis drop & swaybars, bilstein stocks, AR626 & 404 Nitto's, Yank converter, ASM headers, ASP underdrive pulley, Taylor wires , free mods VCN 2000, Nelson Performance tuning
2002 Red WS6 M6; Flow master K&N