I built Lord Luke his first iteration of this rig years ago when he was just 16 Yrs Old. Since then it has been updated and modified more time than Trigger's broom! At first it was a basic rack-mounted router/splitter with mutes. The mutes were controlled via a floor box.
The chassis is then drilled for the new choke, O/P TX if required, new power block and new volume pot location. Four of the valve base pop-rivets are drilled and replaced with screws to hold the insulating stand-offs for the new grid resistor board.
A couple of years ago, I began working on a new Amp for Brian. This was a new design that was optimised around everything he needs and wants from an amplifier as well as increased reliability. A by-product of this research and design is the better understanding of the standard TBX amplifier and how it can be made to really 'sing' in BM mode whilst still being reliable.
So during a coffee break at Allerton Hill one day with Mr Malandrone, the conversation went along these lines: Pete: Any chance you could knock-us-up a small version of Brian's rig that I can fit in the back of my truck and lift-in on my own? Me: Sure! When do you need it by? Pete: Oh, no rush!.. Me: OK!