What is this bolt/nut/clip called and where could I find a new one? As the title says, it's the bolt that holds the heater core to the firewall. It's a 1989 r3500 with a/c (doubt that matters tho). I broke one when removing it and would like to replace it. I know I could go searching in a junkyard or rig up something with a carriage bolt but would like an actual replacement if possible. Thanks!