Plenty of options to fit an aftermarket sensor, have removed the factory water pipe from the thermostat housing and tapped that out to 1/2 bsp to run a proper pipe with -6 fittings to the turbo, also tapped under the thermostat so I can run my factory dash coolant temp (66 XR Falcon). This runs true engine temp not after the thermostat opens. As the fuel and other maps are corrected by engine temp it needs to be accurate.
the haltech(Commodore) sensor is only $50, I thought they were more than that so may go to that if the factory one doesn’t play ball.