Lloyd,
If you haven't already come visit us over at:
www.gt40s.com
GT40s.com
you may already be on though. Bob P will certainly know if it will fit or not, but for most of the GT40 replicas one of the Victor Jr.s won't go, carb too high.
There is a recent Muscle Mustangs and Fast Fords which compares all the intakes on a stout motor, the single makes a little more top end but gave up a lot down low. But, in a light car you'd probably never notice it except at the track.
Ron