70 Swinger Dash lights

The flasher should be just to the right of the ash tray, should be able to, with the face of your hand, reach up and back with your fingers and touch it. It's in a little cupped strap that holds it.
As for your bulbs, you may be taking your seat out, and your steering column, and loosening your panel screws, what ever it takes. The speedo is not that hard, it probably needs to be greased anyway.
The radio has its own light bulb, it's on the top. You will have to remove the radio.