I have a major problem for you guys.  I just bought a fully spec'd Colt AR-15.  It has the original A2 stock still on and I bought a new tele stock for it.  I searched the internet for easy installation instructions but found none.  I finally figured out how to remove the stock and the spring tube.  I made sure that none of the springs and the pindel did not go flying out. The only problem is that when I installed the new tele stock that I screwed it in too far and the pindel locked about 5 threads back and now I cannot remove or turn the stock.  The upper will not fit correctly with the lower.  What can I do or do I just have to cut that stock off and break the threads for that stock to get the pindel free. Also-how do I remove a bull barrel and hand rail to change into a M4 spec.

I'm trying to figure out what a "pindel" is.

As for doing a barrel swap:

1. Remove the handguards.
2. Separate the upper and lower receivers, and remove the bolt carrier assembly.
3. Drive out the gas tube roll pin in the front sight base.
4. Pull the gas tube out of the front sight base, and work it free from the rifle.
5. Remove the barrel nut with an armorer's wrench, and pull the barrel out of the upper receiver.
6. Apply moly lube to the receiver's threads, and slide the barrel into the upper receiver.
7. Torque the barrel nut to 30#, then tighten it however much more you need in order to install the gas tube through a notch in the barrel nut.
8. Reinstall the gas tube and hanguards.

The pindle is in the lower reciever where the stock threads are and holds the recoil spring into the stock.  It has a spring under it and
when the spring tube is removed that pindle with spring can come out.

Quoted: The pindle is in the lower reciever where the stock threads are and holds the recoil spring into the stock.  It has a spring under it and when the spring tube is removed that pindle with spring can come out.

Okay, you are referring to the buffer retainer.

When you install the receiver extension (buffer tube on the telestock), you screw it in until it overlaps the edge of the buffer retainer (but not over the pin part of it.) This keeps the buffer retainer from popping out.

Let's see if I understand what you are saying. You've tightened the receiver extension too far into the lower receiver. The buffer retainer was depressed and allowed the receiver extension to go in farther past it. Now it it locking up the receiver extension and you cannot remove it. Correct? If so, you might have to try to find something to stick in there and depress the buffer retainer even more so that you can unscrew the receiver extension. Otherwise, you'll just have to manhandle it and force it off. You may damage the buffer retainer in the process, but it's a cheap part.

So once you got the receiver extension in far enough to capture the buffer retainer pin (pindel,) you turned it another 5 revolutions and it is now stuck?  I'm trying to picture 5 more turns being enough to get it stuck and it being so stuck you can't "unstuck" it...

ok i'm back.  I just checked my rifle.  I am using an LMT receiver extension on an RRA lower.  Inside my lower, there are at most 4 more threads to go before the tube would theoretically start carving it's own into the lower.  There are no real threads left though, they are all partial either due to the pin hole or the cutout for the internals.  The extension on the other hand has ZERO threads left.  This LMT has what look to be 5 more threads that were turned down a little so that they no longer have the peaks, just the troughs and can be threaded into the receiver, but not engage anything.  They look like they were stripped but are factory.  

So, what you've done is run out of room and somehow jammed your castle nut and buffer tube into your receiver.

Are you using the backing plate?  I can't imagine you installed that part because it would have stopped you dead in your tracks...

Ok.... I finally got it to come out.  Tonight I was messing with it and with a little lube down the back side of the stock I managed to get a small piece of flexible thin metal stripe down the (gutter) of the stock. I depressed the buffer and was able to remove the stock to my relief. Yeah, I know it was kinda stupid but I dont have a lot of experience with the AR and they never sent any kind of instructions as I stated before.  Thanks for your help!

glad you got it out.  Had you forgotten the back plate after all?