This has probably been covered many times here so I apologise if I'm retreading old ground, but was the detuned Wild Honey piano a grand or an upright? It sounds more like an upright to me.
Also, what exactly was the harpsichord used on Smile? Was it an electric Baldwin? It sounds like one but the photos of Brian and Van seem to show what appears to be an acoustic instrument.
Mostly on Wild Honey, it was Brian's Chickering Grand, which was a gift from his Dad.
It seems that the harpsichord they were using was some double-manual job, certainly with a buff-stop. I haven't seen enough of it to determine much else--though I guess at that time the harpsichord-maker market was probably less widespread than it is now, when you can order pretty much any kind of harpsichord you want.