With your VDO
oil gauge, does gauge go full scale if the sender wire is disconnected while the ignition is on?
If so, 0 ohms if be zero
oil pressure and about 250 ohms would be full scale.
If you have any doubt on the electric gauge, I would fit a mechanical workshop gauge prior to fire up.
I fitted another
oil pump on a VE last Thursday after it developed no oil pressure at another shop while having a service (oil and filter change).
Pressure relief valve stuck open in the pump.