You could go crazy and do a dual downdraft 4 carb Weber system with short stacks. Does your mockup have heads? I've never seen one, are they plastic? Anyways, if they do you might be able to get the measurements to fit these. I mean it's only money right? You can't take it with you so you might as well enjoy it now. And what a better way than the coupe. That's what I keep telling the wife. LOL