Deluxe Dirt Finder Light?
As far as I'm aware, the Junior Deluxe Model U2068, which was available either in a yellow/black or green/ivory colour scheme, didn't come with a headlight as original equipment. However, the similar looking earlier Hoover Starlight Junior model U2002 did do. This machine was made in either a red/ivory or blue/ivory colour scheme..so I don't know if you have some sort of hybrid Junior Deluxe/Starlight recon or if it's a Special/Exclusive that I haven't come across. I know that there were one or two of these made.
It's a while since I last stripped one down but on the Starlight, you should be able to access the bulb after removing the motor cover plate, in which case you need to lie the cleaner down flat and remove the cover plate screws and pull the cover off. It should be possible to do this without removing the lower chassis from the machine. The bulb will be a small pygmy type. IIRC, there is a little pivoting reflector shield, which moves as the handle is raised or lowered. This is because the lightbulb is fitted in the lower backbox so the direction of the beam changes with the positioning of the handle!
I don't believe I've ever had any instructions for one.
Oh and similar instructions apply if it's necessary to replace/bypass a blown up capacitor!
Stephen