I'm trying to figure out what center caps I need for the blade style 1989 Honda Prelude alloy wheels. I purchased ones on eBay that allegedly fit, but they don't, they're too big. I suspect that they're for the 1990 Accord 15" wheels. The factory center caps from my 1989 Accord Rims fit, but they're slightly convex, and I'm not sure if the prelude center caps should be flat, or if they're the same, just with a different finish.