I've remade the hinges from brass (with the help of my friendly milling machine owner). They were machined down from brass square to a rectangular profile, turned on the lathe to make locating pins and then shaped with a files.
The hydraulic cylinder brackets are also brass and the hydraulic cylinders made from aluminium tube.
The mechanism is a mini servo with a borden cable attached which runs out of the wheelhouse and then through the 'dummy' hydraulic cylinder. I had to modify the servo mounting as it was too low and left too much unsupported bowden cable. I'm also not convinced this mechanism is robust enough... Even with an Action Servomorph, there's not quite enough travel to lower the mast fully so it's supported by the dummy hydraulic cylinders - the while weight is on the bowden cable. So on a drive to the lake with the mast lowered (as it's too tall to fit in the car, the bowden cable kinked and so was then useless. I've since tried brass rod but it's too stiff for the servo to drive. I've since found that With the mast lowered slightly it will fit in the car so for the time being, I've reverted to a replacement bowden cable. I'm hoping that with the mast lowered only a little, most of the cable will be supported and so is less likely to kink; time will tell. Otherwise, the only idea I have left is to make a linear servo as the bowden call will then run on a straighter line rather than the arc of the servo arm.
Anyway, here's a video of it in action...