Originally Posted by Partsmke
Unscrew it out of the block if it is in the water jacket it will allow coolant to escape. It does appear to be a capillary style temp gauge (mechanical as opposed to electric).
Yes, the TBI coolant sensor uses the front right coolant port on the intake manifold. If your CJ is running a mechanical coolant gauge then the block drain plug port would be where it was moved to. If your CJ has the electrical gauge hooked up it uses the small coolant port on the front left of the the intake. Do you have the stock intake manifold or an Edelbrock?