If you want something better than regular parts store wires, you might have an issue finding them for a straight 6. They need several very short wires, and I have doubts that you'll be able to find an off the shelf performance wire made for them. Custom fit may be your only option for a 300.
And I can stand in the engine compartment of my F series trucks with FE's in them, but I'm only 145 lbs, so that probably helps a bit..lol