There's a few companies making the long tubes. Besides Hedman and Clifford, Dynomax is another one and there's a P one. Pacesetter maybe?
Anyways, if you ever plan on lowering your truck, the long tubes most likely will be problematic. I've not yet installed the front air spring suspension so with the current static lowering, I can't even get in my own driveway. Occasionally they scrape on speed bumps and stuff. Something to think about. For about $150 more you can get the cast iron shorties that will last much longer.
And definitely take Richard's advice about the studs. It's frustrating as heck positioning everything otherwise.
