Thanks Ross.
It took a couple of evenings work to hand drill it and the drill actually came through the side near the inner end - I knew that when the sawdust appeared on the drill.The metal is not great quality, not quite Mazak, but quite aerated, so it does drill quite easily. I added a small stainless washer under the replacement post, and did the same on the other side. Both mine are angled slightly upwards, and it was in a moment of stupidity (just a couple of taps with the hammer to straighten), that it snapped off. Then I got that pit of the stomach feeling..........
