iirc thats the compressor & expander - you can run the both simultaneously, which is kinda wierd... I carried out that mod on mine after I got fed up of the multi-leaf jamming up, and prior to my err... mods...
I see what you mean, Eric... that was an early one... bummer...
I prefer the colour of Uwe's CMT, but they both are beauties...
Soon as I finish my Peter Cook I'll be doing the RD's refurb...