Coolerman, I responded to your other thread. But I'll comment here. The dome light and bracket you have are identical to my 4/73 hardtop. I didn't know you had a soft top. On mine the lamp bolts to the bracket with two small bolts. One of which is the ground, as your picture shows with the white/black wire with the little bolt still in it. Off the other bullet plug on the wire in that pic, a short run of probably Red/Green wire ran to another bullet connector like I described in the other thread. This connector was present at the top of the windshield frame. The wire passes through a small hole in the top of the frame, from the under side of the frame near the glass where the wiper harness turns and follows the frame over to the motor with the little clips.
My 4/73 factory hardtop does have a hole in the dash for the ST dash light, but is factory plugged with a palstic grommet. This is to the right of the glove box. Right beside this, is my factory dome light switch. The small round handled pull switch. Why it is clear over there, I don't know, pain in the butt to get in, in the dark and lean across the dash for some light if needed. But I kow that was stock location. There is a second hole, near the ashtray, that this dome light switch would also work. I thought on ST, that the switch was located there. However, I don't think the wires will reach there on mine, never tired. But the switch is always hot. From the switch I have two wires with bullet connectors that leave it. One ties into the wire in the dash loom that eventually ends up at the top of the windshield, Red/Green I think. The other was just empty, stock. I have since added an old liscense plate light I had, to a cover plate and mounted it in the glove box where the speaker hole was. So now I have light in the glove box too.
I'm currently morphing into a soft top, with an Ehsan top. I'm planning on putting one of these into the dash hole
SeaSense Livewell Light - Lights - Marine Acc. - Marine & Electronics It fits the hole great. Easy hookup. Just haven't done it yet, I'm not sure how well it will distribute light in the cab yet, but being LED will be a plus, and waterproof.
The bows you have pictured have the later style, dome light in it. This would not be what the earlier body style had. That is neat though, and could easily be done. I don't know exactly how that light gets the wire routed to it, either on that bow or the hardtop, never messed with a 75 and up in that way. They have the switch right on the light though, no dash switch.