I recently had to send out my left tank fuel gauge for repair. Upon getting them back and reinstalling, my mechanic observed the fuel gauge fuse blowing once the gauges were reinstalled and the master switch turned on. We reviewed the manual and noticed a part was missing for us in the reinstall process. When securing the gauges to the post on the airframe there is an “insulator” in the diagram for each of the four terminal posts that attached the gauges to the airframe. This insulator appears to stop the metal posts from touching the metal airframe attach point (and causing the fuse the blow). When uninstalling we did not observe these insulators. We looked everywhere beneath the connection point to see if they fell down into the aircraft (no joy). The parts manual (figure 28-2) shows this insulator but doesn’t give a part number. I need to have this part number to order four of them for the reinstall. If anyone knows of this part please pass it along. Thanks!