Yes upgrade to 7"x H4's with strong halogen plus 50 bulbs, and the parking lights in the headlamp housings.
Fit a relay for these improved headlights to save overloading the sensitive headlight switch.
Then you can use the lower small lights for turn indicators only, and fit amber globes or lenses. Much safer.
Regarding the front number plate, if it's like a 66 you just pack it out with lengths of 3/8 tube, fibre tap washers and long metal threads, or make up aluminium brakets out of something suitable from the Bunnings metal display.