How to incorporate resistor into harness

How would a professional incorporate a resistor into a harness? Seems like all resistors are soldered. I'm concerned about strain relief. To give context I have to use a resistor in an oil temperature circuit and a momentary switch circuit.

If soldered resistors and their connections are completely enclosed with adhesive-lined heat shrink there won't be any vibration / strain issues. You could pot the connection as well. Either way you basically end up with a lump that has 3 or 4 wires extending from it. it can be hidden in a transition or with a connector boot.