[OJFord]

> IIRC The manual contains circuit diagrams.

It does, I bought one (new, latest model) recently and was thrilled to see that. I've bought ~'80s amplifiers on eBay and loved that the manuals have circuit diagrams, and thought it was a lost era.

The Silvia's is far simpler (to state the obvious) but a wonderful inclusion.

Even though it's fairly readily determined, given its simplicity, it'd make me more confident in any repair or modification.

The one I have been thinking of is replacing the pump and reservoir with (a pressure reducing valve and) an electronic valve plumbed in, so that I never have to top-up, or risk the boiler running dry.