PVC, if it is old or has seen cycles of high and low pressure, can become brittle, which may explain your previous failure. Cardboard is generally not thought of as being very strong, but it will not go brittle as PVC can. Cardboard is by far the most common material for mid power body tubes.
Another likely cause of your PVC tube failure is an excessively large ejection charge. What did you use (black powder or something else) and how much, for how much volume of tube to be filled?
As for your original question, if you are installing a bulkhead to anchor your parachute to, where will the ejection charge be? You would need to have, from bottom to top, the bulkhead, the ejection charge, some sort of 'chute protector, then the 'chute. I'm just checking that you've thought that through.
For attaching the parachute to the bulkhead, strictly speaking you don't. The nose cone (or as much of the top of the rocket as separates from the bottom) is attached to the bottom by a shock chord (that is, some sort of strap or other rope-like thing that is capable of withstanding the shock when it suddenly pulls tight, and preferably of absorbing some of the energy to mitigate the load on the rocket bits at its two ends) with the parachute's shroud lines attached to the shock chord. Attach them about 1/3 of the way from one end so that the rocket bits at the ends are not bumping against each other.
So, the real question is how to attach the shock chord to the bulkhead, not the parachute itself. Actually, for what are classed as mid-power rockets the bulkhead is likely not necessary as you can attach the shock chord to the forward centering ring (CR). There are typically two ways to do this. One is to pass it through a hole in the centering ring that is just large enough to let it through. Make the hole close to the motor mount tube (MMT) or even use a slight expansion of the inner MMT hole in the CR in one area. Use epoxy to fasten a several cm of the end of the chord along the side of the MMT, and to fill the hole. And that's it. (In low power rockets something similar is often done. The shock chord is much smaller in these cases, so it is passed around the MMT below the forward CR and tied to close a loop.)
If you must use a bulkhead, you can tie the shock chord to either an eye-bolt or a U-bolt. That's what's typically done for what are classed as high power rockets, though when I say "tie" I'm leaving out a bunch of details that are important for high power builds. You can also use an eye-bolt or U-bolt in the forward CR if the difference between the body tube and MMT diameters is great enough.
