Morning Andy, now ive ventured into the shed and the hamsters re spinning in the pc I can get some dimensions from CAD.
Just as well as its snowing here in Worcestershire, so dont fancy rolling on the floor.
Below is an overview of my chassis accepting RX8 suspension.
A similar concept to yours but for a different purpose.
Mine has been calculated from the floor using stock RX8 wheels, and has been set up so the centre of the diff shaft holes on the back allow the drive shafts to be completely horizontal at ride height.
Also the steering rods on the rack are set so they dont have any bump steer.
I dont know how critical to want to be but my CAD is set with stupid decimals tolerances.
So for clarity, Front subframe, bottom arm pivot point on the front mount, hole centre is 172.5mm
Rear subframe, rear bottom arm pivot point, hole centre is 172.25mm
I hope this helps?
Good luck with the build, keep the thread going