That looks like interesting stuff, AstroDad. I'm going to look into it a bit deeper.
A method I have seen used by a couple members on this forum involves using Tamiya clear orange brush painted over light brown or 'wood' colours. I don't recall the details of the technique, but brush lines are purposefully left in the clear orange paint simulating grain. The effect was very convincing, giving a nice glowing varnished look. A search of the forum might turn up more information on this.
My personal favorite method of applying wood grain to dashes and consoles is to look through catalogues or flyers for wood working tools or lumber yards, speciality hardwood shops, etc and finding photos of wood grain with suitable grain & colour in them. I cut out the wood grain photo in the shape needed and use Microscale Foil Adhesive to apply the wood grain photo. The thinner the paper the better the image will conform to irregularities of the plastic part. Also, keep in mind that the colour of the plastic part may somewhat effect the resulting colour of the finished wood grain once the adhesive dries. I would think this will work on a pick-up bed too.