Well the GpzZone tool didn't work for me. It looked exactly like on trangwales last pictures after hammering it in to the rod, but the rod kept sliding around it.

To be fair, note that i don't have access to an impact gun.

So i decided to try an even cheaper route (and i wish i started with it ). A very logical route may i say, i'm surprised i could not find it on the net.

- Get a metal tube (or square tube), that goes with some room inside the rod (i took 12mm steel tube, 1m long, could be a bit smaller)

- pierce it to 4mm about 20mm from the end, tap the holes
- pierce as large as you can on the top (optionnal)
- screw a 15-20mm M4 screw in the small hole (the larger possible screw that will fit in the inner diameter of the rod)
- put a bar/big screwdriver through the big hole (or simply grap the bar with locking pliers)

yes you got it.. slide your "tool" in the rod, swear and try until the screw gets frankly inside one of the compression holes at the bottom of the rod (marking the screw direction at the top of the tool helps a lot). Well done, now you have a firm grip to the rod, you can break the screw loose.