G2 boiler handrail mysteries

I've been looking at a lot of photos of steam trains recently. Mostly Super D's which have been in front of many snappers lenses. All with a mounting sense of frustration. You see I was trying to work out how the boiler handrail works.

On a normal engine it's simple, handrail knobs of varying lengths support it out from the boiler. You drill some holes, bend a bit of wire and after a lot of fiddling and swearing, the job is done.

On the G2, it's a different kettle of fish. The handrail runs along side a fat pipe that runs along the boiler. Trying to get a clear view of this is impossible. The plan helps a little but in photos the rail is overshadowed by the pipe. I would guess that there is some clever bracketry going on to hold the two but I can't get a decent look.

In an effort to progress this model, I've had to make an educated guess. The pipe was soldered into position and then drilled with 0.9mm holes to take some split pins which will act as handrail knobs.

There was still much fiddling and swearing, not helped by the fact that the longest bit of 0.7mm wire wasn't long enough for the whole job so I had to hide joins in the front split pins, but at least it now looks OK.

Update: Of course, now I've done the job, I find this photo on the NRM website. Amazingly, it looks like I got it right !