As a modeling light, a small flashlight velcroed on to the flash should work fine.
Thats what I was thinking. I have a couple of LED lights I got from Costco that came three in a pack. Do you think they over power the flash? It looks like white light so it shouldn't give color film an aweful look. What do you think?
A small flashlight will give you far less light than almost any electronic flash - unless you use really long (several seconds) exposure times.
Be careful about using them as modeling lights - it will be difficult to set them up to illuminate your subject in
exactly the same way as the flashes. In addition, if they have a tightly focussed beam, they should be diffused in order to ensure comfort for any people in your pictures, and to give you a better sense of how the edges of your scene will appear.
They should be fine to give you enough light to focus.