i just took a piece of hose from a water pump clamped it on and then took a bolt big enough to fit in the hose and clamped on that, and I havent had a problem since. i wouldnt just smash it cuz, if you ever want to sell it it could be easier to sell it with the smog fitting operable.
I have the same pipe, what I did was once it was in I welded the 2 pieces together this way it'll never leak, I also cut the hangers off the pipe and rewelded those to make it fit a little better. as far as the smog tube, what I did was take a bolt where the head fit inside the tube held the treaded end with vise grips and welded it in then cut the excess off