if you really wanna try it, get yourself measurements of various scoops and make a whole boatload of em outta cardboard.
I really wanted to do the old superstock scoop for mine, so I fabbed one out of cardboard. Lemme tell you there is somethin about that superstock mopar scoop that makes it only look good on a mopar. Its friggin huge! The proportions of the mopar hood just fit the scoop better. On the wrong car....it looks like it overtakes the entire hood.
So...I went and found the measurements for the scoop pictured above(mercury cyclose, boss mustangs and varios other fords or ford related use that scoop or a similar one).
Took some tweaking, but I eventually made a model that was proprotionate to my hood. Then I just made it myself(im stuck with a steel hood and had a hard time finding much of anything that wasnt fiberglass). Hence the reason i made my own(didnt want glass on a steel hood) so i made a steel one.
Id be willing to bet you're gonna be like "wow the mopar looks all wrong on this car" just cause of its sheer size. Make a model first so you dont end up dissapointed in a purchase.
Here is the pic of that scoop above(I beleive that scoop above) on a 67 chevelle that inspired me to go a little smaller than the mopar. It looks better on a GM than the mope does. Not sure whos car this is, but I thought it looked good. Ive got a 66 GS so I was limited in hood options. Mines a little taller in the back because I actually needed one for hood clearance. that one "as is" didnt provide enough for me.