Beau,
The light you describe is really meant for use as an on-camera light for news style reportage and to illuminate a reporter “standup”, not for portraiture like the oral history interviews you describe.
You have the right idea by doing them inside, away from the harsh light and heat outside, not to mention extraneous noise. Your best bet would be to stage the seats and the camera in such a way as to take advantage of some nice diffused window light; either north light or through white curtain, while keeping the background darker, or at least devoid of other windows.
If you are forced to use artificial light, because of the layout of the interior or night-like conditions inside, you should consider a twofoot fourbank kino or a quarts light inside a small chimera. These make excellent keylights for portraiture. A typical portrait kit would also include a backlight for separation from the background and perhaps a fill light, although with a soft source this is not always necessary, or can be accomplished with a white card. In addition, a splash of light or color from a source four or similar unit on the background often is a nice touch.
It does not seem however that you’ll have access to this type of equipment, so really your best shot is to get creative with the available light, which means staging the action to take advantage of the light that naturally exists. This can often be very successful, especially when dealing with “non-professional” talent who might otherwise be intimidated by having a bright light in their eyes.
Good luck,
JS