Some news at last from Spanner Monkey Island!
Looks like the idle beast has got off his big blue arse and started fiddling with metal instead of his balls... It's 3mm mild steel with an anti-corrosion coating apparently.
Anyway, the 4 shapes on this chunk are the front mounts for top and bottom wishbones. These will sit around the chassis box and be welded to it. Top mount is level with the outside of the chassis box, bottom mount level with the inside.
Monkey boy reckons he's been a bit radical with the anti-dive so the bottom wishbone front mount is 100mm down from the underside of the chassis.This apparently angles the lower wishbone down at the front so that under heavy braking the 'bone is not acting parallel to the chassis, thereby reducing the load that the suspension receives. This could also be done by angling the top wishbone backwards, but my hairy friend never felt that was very efficient.
The other shapes are the balljoint mount plates. these will have reinforcement gussets around them. The lower mounts will be tied in to the coil-over bottom mount.