Hood scoop question

Looked around and couldn't find anything, what are the dimensions (mainly length and width of the mounting area) of the dual-snorkel-style hood scoop like was on the later Dusters, Dart Sports etc? Not the twin scoops like on the earlier models. I'm looking at buying a scoop from AAR Fiberglass but I want to get an idea of how big a hole I can cut in my stock hood since the engine is offset but I want to mount the scoop centered on the hood.