Forget cutting the steel braid, just wire tie it to something.
JB weld works great for this little problem. Just forget about the washer and all that nonsense. Put a bead of the JB around the hole, and stick the nozzle on top of is. The opening of the nozzle needs to just pass the inside of the pipe, or be even with it. Once the nozzle has set where you want it, re-inforce it by installing a taller bead around the outside, so the JB makes more contact with the up pipe. Wet your finger and smooth it out.
Now there are no obstructions at all. A hammer and chisel will be needed to remove the nozzle, if you ever need to. It's not too difficult of a job to do. I've done it several times with a wood chisel.
There is nothing wrong with the way you are trying to do it now. Seal the job with JB Weld when you are finished if you suspect leaks, or use a neoprene washer on the inside.