Anyone my ranger the inside cab light stays on with doors closed

Try removing the rubber cover on the door switch and spraying with WD-40.

What year is it? Late 90's and newer do not have an external door ajar switch to try and clean. The switch is inside the door and clips to the door latch assembly. Do not bother trying to clean this switch. Its about $25 at any decent parts store. Stay away from the "zone". Very very very common part to go bad. Drivers door is more likely to stick than passenger door but either one can do it. You have to take door panel off to get to it. Easy repair if you take your time.

Good article on the subject

Ford Door Switches keep interior lights on (http://www.ricksfreeautorepairadvice.com/repair-topics/body-paint/ford-door-switches%E2%80%94a-known-problem)