After seeing Gary's header tank upgrade, I couldn't resist. So I got one, and a battery tray from Alloy Racing Fabrications. This now allows the bypass by the thermostat housing to return to the header tank, meaning that I've got a small amount of flow while the thermostat is closed.
At the same time I used one of their fantastic, lay flat, battery trays.
While I was at it, I've never been happy with the fuse box location on the scuttle. It leaves the wires showing, I like to keep things looking uncluttered so I've cut a aperture in the panel and sat it down in with rivnuts to bolt it down. Plenty of space between the gearbox and wiring underneath. Quite pleased with the look I think...