The instrument cluster temp gauge on my 74 ,304 would not work when I started up the jeep after several years in storage. I had a new stewart warner mechanical temp gauge from another project. however the fitting on the capillary tube is way too large to fit the hole where the orginal electric sending unit was. The original electrical sender looks to be about 1/8 pipe thread and the analog tube looks to be maybe 3/8 pipe thread. The electric sender unit hole is so small even the bulb on the mechanical capillary won't even pass thru, so an adapter will not help. My question would there be somewhere else in the water jacket that have a larger access point? It seems all the mechanical gauges sold have the same larger fitting. ??