OK 07+ guys, I got the pvc pipe bomb to work.
Several tricks to the process that I can give to those that aren't used to dealing with pipe, or trying to turn something in a pressure vessel.
First, like the diy says, use the 3 inch pipe. For padding, I just used paper towels. They are in there tight enough that I don't think it'll break down, as nothing moves around. I ended up heading to Ace Hardware and got a brass valve stem. I couldn't get the rubber ones to seal well. I drilled the hole in the cap to 1/2", then smoothed it with a round bastard file. It was just right to self-tap and thread on in. Then I put an o-ring on the inside, and then the nut. That should give you a good seal there.
One last thing- remove the valve core when you put it all together, to give the air a place to go when you put the last end cap on. You can end up with a small air hole through the glue if you don't. I hope this helps someone save a couple bucks over what I spent. But it was an excuse to buy more tools...:naughty:
BTW, it was still cheaper than buying a set of sensors to fit the new wheels.