How to ask for Sponsorship

The sun is coming out and racing season is getting ready to start. I have always footed the bill myself for occasional weekend racing. This year I am going to ask for some sponsorship help. I work at a car Chrysler dealership and mentioned sponsorship to a mid to upper management person. He said to type up a proposal and submit it. So I have never done this before and am unsure on what to ask for and how to present my car as an advertising opportunity for them. What are your experiences and suggestions. Car is a sportsman class bracket car. 69 Dart swinger. Low to mid 12s with best time of 11.89 back in 1989 lol