The added shrink sleeve over the skirt will give support (as in fulcrum support) and some pull-out strength and vibration resistance. Plenty good enough for your truck. If you have applications for wiring onto a stud or for a screw, use only ring tongue, never spade. You can get shrink sleeved terminals as Bill suggests. Here is some more info to keep you awake. There is a special, original style, right angle, insulated terminal used on the gauges. It slides onto the stud. They came with my American Autowire Kit. Don't know who sells them. Proper tie wrapping, harness design and clamp spots will eliminate most vibration and provide strain relief. Use many small zip ties along the branches no matter how big or small the bundle is. It makes a real nice looking, round, more manageable harness. Try different routing to assure no chaffing or pinching and provide serviceability. As goofy as it sounds, I do like liquid tape for high moisture environments/locations. If you are worried, just test your crimps, pull on the terminal or on the wire and see what you think. There will be no problems.
