Thanks for the encouragement Bt, it has some tinkering needed, but I think it's doable. First step is the thumper, then I'll give it a go.
Just had a bitch of a run, Paris wouldn't co-operate. First there was a leak in one of the sight glasses, then the plates seemed to be flooding... then after about 2 hours of taking off spirit that smelt like heads I gave up.
Packed everything up (noting that the bottom plate took ages to drain down and went inside for a drink, after which I remembered that I'd left a piece of wet cloth in the bottom downcomer when doing some resoldering.... pretty stupid mistake.