i have a 1989 dodge dakota and can find very little information on ways to customice the truck. I can't even find a company that makes headers for this year dakota v6 3.9
i have never seen an article on this truck being customized.  

Custom Classic Trucks' cut-off date is at 1987, and we don't cover mid-size or mini-trucks, but I don't mind offering you some advice that will help you out. Instead of headers why not go to a high-performance exhaust system like a Gibson or a Magnaflow? Also there are companies that make lowering kits for your Dakota, and custom wheels & tires. You Dodge guys have a tough road, I know I have an '86 D-150 shortbed we have tech featured in CCT. Here's another lead that will help, get a hold of Calin Head over at Sport Truck magazine through their website, or Mike Alexander at Mini-Truckin' the same way. Both of these guys are cool dudes and they should be able to offer you some more ideas.