What year magnum? The pre 97(i believe) have two ports for temp sensors. One for the pcm and the other for the gauge. If you have the later magnum you can use the earlier intake and have a port for the sensor. Or dill out/tap where the sensor would be on the newer ones. In the pic below you can see the port to the right of the water neck.

[img]https://www.forabodiesonly.com/mopar/attachments/dscn2602-jpg.1714624222/[/img]