Well, for those of you not so bored that you have wandered off, this is taking shape. The boards are finished and attached to an ally bracket, the heat sinking arrangement is sorted. That was a nice bit of engineering. I am now sorting the PSU, it came in a case which I have had to modify. The thing that's surprising me is the amount of time necessary for these one-off engineering jobs. As an example, there should be 10,000uF caps on the boards to smooth the power input. They are too tall to go in the case. No problem, I'll just mount them on their sides and devise a means of connecting them to the BR and the boards by flying leads. Pom pom pom, tumtitum, OK, I'll do it this way...need to be able to test the boards without unsoldering everything or doing oceans of disassembly...tumtitum...oh there goes 2 hours. It was the same with the heat sinks, I reckon I must have spent an afternoon sawing the heat sink to fit, and that was after the angle grinder had decided to let the magic smoke out. I now have a newfound respect for people who build one-offs or short run items for a living, the cost in time is significant.