MGB in the workshop

The sharp eyed amongst you might recognise this MGB from when it came in a year or so ago for somewhat of a major overhaul. The owner reports that it's driving great and constantly putting a smile on his face but it's developed a rather ugly but intermittent grinding sound whilst depressing the clutch pedal. I have reproduced it, I'm going to have to take the engine out and have a closer look at clutch, flywheel, throw-out bearing and spigot bushing, it can't be much else. At least it comes out easy enough, I've only just put it in, relatively speaking.