The clutch slave failed – not sure why, perhapse the master cylinder was a miss match or it was just a bad part. The reason is not so important.
I’ve decided to use the BMW master cylinder as this will be matched to the slave. Unfortunatly the original design for the clutch attachment is very poor – the whole pedal box twists.
Therefore I’ve started protyping a new bracket design that will be a strong mount for the master cylinder with a bracket the bolts up through the top of the scuttle – already re-enforced for the pervious alternative clutch arrangment.
I’ll 3D print this bracket for test fitting and if it works OK I’ll try to recreate it in aluminum.