Hi,
More information about your light box, sources of illumination, and the end effect you are trying to achieve may help people give you useful advice,
if you are looking to just show detail, multiple light sources (or reflected light from different angles will help remove shadows that hide detail,
but if you are using multiple light sources, be warned the colour of the light may vary and may make your paintwork look discoloured,
(eg sunlight on one side and a fluro on the other will tend to make the fluro side 'blueish' or the sunny side 'yellowish')
I have used a pair for work lights (from a hardware shop) on either side of an home made light-box in the past, with reasonable results.
Also changing the distance of the light changes it's intensity, so you might want to play with that and the direction of the light...
Hope this helps get you started.
Regards,