The channel around the door on the inside of the cab needs to be straight. Take out dings and kinks. Put the rubber through the top part over the door opening first. Don't cut the ends of the rubber until it has a chance to relax, your stretching it a bit while pulling it into place. Follow directions on the weather strip adhesive for the door rubber. Don't close the door till the adhesive cures. Do all the work in a warm place. Take your time, you'll be living with the results for a long time.
