I bought a blister pack of zirks at the auto box store and it had two each plugs, straight, 45 and 90 fittings. Your local parts house should have a little plug, unless they have to have a year and model application to look it up They're a common fitting. I think I would be concerned with that crossmember height, too. Mine hits a coke can right at that top shoulder where the straight side rolls over, almost twice your height, and I take speed bumps really easy, as well as curb dips off of the street. Taller tires will help, but you might also think about running 16's or 17's combined with the right tire to get the clearance you need. That would help your grease zirk problem, too. It's getting harder to find 15's all the time, but Coker loves us running them $$$$$