Andy, would you be able to tell us what the upper inside front fender of the '57 Ford actually looks like? Revell's Del Rio still has that low inner fender well that interferes with lowering the model (and would seriously impede suspension travel if it were a real car!)
It's been a long time since I had my last real '58 Ford, so my memory's not quite clear on that aspect, but I don't think it had much of an inner fender well, which was why they always rotted out over the headlights.
Does this help? I could take other pics if needed.
It looks as if the Revell follows the fender opening and is too low above the upper control arm. As seen in the second pic, the inner fender is above the trim line (note the hole for the trim)
There is about 3 1/2" from the flat area to the fender lip (area behind washer bag)
on the 1:1 it would be able to lower the car a good bit, but eventually would interfere with the tire.