if you want to get really goofy, you could take the map light out of a mid 80's Mustang.. they had a goofy thing that looked like a flashlight that you could point wherever you wanted.
another option would be the entire overhead console out of a mid 80's Camaro. my 86 Camaro is a t Top car (booo) and has a console up there that goes all the way from the windshield back to the middle of the roof, with the dome light built in. it's mission on mine, but there is supposed to be a map light towards the front of it that you can aim wherever you need the light.. plus, there is a useless and weird counter thing up there that you can set for various things that looks like it would be a nifty place to mount a Scanmaster with a little fab work..