Just thought I'd post a quick update.

All of the SAM brass has now been 'Stereo Staged'.
Work is well in progress with all of the new GOS library, with the stereo stage inserted into the sfz files.
XML next.
The new Choir is in a similar state to GOS.
I became briefly sidetracked when I realised that the new 'Custom Organ' didn't have a stereo stage.
There was a minor problem there in that cc36 was being used for the left most 'organ stop' to adjust the level.
So I had to move them all up by one (missing cc38 for some reason) to release the depth control.
Here's the resultant controls GUI. I had to move the Instrument Controls up a little.
It's a little crammed on the right hand side, but I think it's understandable which control does what.

What say you?

I'd hoped that I'd be further along by now, but life somehow has a habit of getting in the way.