To ease the under-dash uncomfortability, I use a 5 foot long piece of plywood which is the right width to fit between the front of the door opening and the seat base. You will need to come up with a saw horse or a stack of something to support the outside end of the board outside of the truck (my air compressor is the right height and when it comes on, it provides a soothing vibration for my chronic lower back pain
).
