Post some pics!
The stock blower can be safely spun to 23k. Plenty of guys spin them faster but its an "at your own risk" thing. Here's a chart to give you a good idea on blower speed with what combo of upper/lower pulley and how many lb's of boost you'll be around. Of course how much boost depends on other mods and what elevation. The very top is you stock pulley combo. Note that certain pulley combos call for different sized idlers as well. A 10.5" lower can be done but comes really close to the A/C lines. Stay away from metco pulleys, they just had a "bad batch" go out and are falling apart on people. The upper pulley neeeds to be pressed on so choose a reputable shop.
weapon X motorsports — LSA Available Pulley Combos and Supporting Mods Needed
Cam-the lingenfelter's seem to cause lifter failure a lot. The ramps are too aggressive. If you want 100% oem drivability they've been using the ls9 cam. But if you're in there doing a cam, might as well get one that has the same manners but 30 or so more hp than the ls9. The only 2 choices I'd make are one of the Brian Tooley Racing (BTR) cams, or an lt1z cam. Both ground on lifter friendly lobes.
The track attack intercooller seems to be really popular too, you can find that on weaponxmotorsports link I privided. That and a norcal box.
Check/change your rear diff fluid if you haven't. Lots of people having whining rear diffs. If its under warranty the dealership will swap no prob. There was a tsb issued to add some additive to the rear diff.