Dome light / roof area?

[imopar]

Hi all,
I was in the process of beginning to install the headliner (73 barracuda, 4 bow) - I was curious as to the brace that goes from one side to the other, that the dome light mounts on, is there supposed to be a gap between the brace and the roof, towards the middle?
The brace is still spot welded on each side above the doors, and to my knowledge, has never been fooled with (it's "possible" the headliner that disintegrated years ago was the original) the closer you get to center, the gap gets wider.
It's probably an inch or less at its largest, but you can push up where the light mounts, and it somewhat flexes back up towards the roof, but I don't see any old welds around the center. Does anyone know if that's normal, or has a weld come loose? 
Hard to see it in the picture, but that is the general area - and my dumb butt figured glue in the insulation first, and ask questions later 
Thanks in advance!

[anlauto]

That's 100% normal. The roof skin is not attached to the braces.

[Surfmichaels]

My 73 isn't attached but it looked like there was glue that had come unstuck in 2/3 locations along the way. There was a little glue (or some substance) left on both sides, I can't say it was factory though because the car was messed with a lot. Anyone else have the same?

[imopar]

My 73 isn't attached but it looked like there was glue that had come unstuck in 2/3 locations along the way. There was a little glue (or some substance) left on both sides, I can't say it was factory though because the car was messed with a lot. Anyone else have the same?

That's somewhat of what I was seeing - it almost looks a little like bondo or glass (not much though) - mine may be where we repaired some spots on the roof before having the vinyl top replaced (20 years ago) - but it did look something near the center and I wasn't sure

[imopar]

That's 100% normal. The roof skin is not attached to the braces.

Thanks, that's what I needed to know; now I can attempt to finish hanging my headliner, and then probably realize I should have gotten a professional!