I was in need of a roof rack as well. The G-Body versions I was finding were off the charts in price. I found one from a full sized-Olds wagon and cut it down. I made the ribs from aluminum strips from the hardware store. I've hauled countless things on this.
If I could magically trade you for your roof panel without the holes, you could have it all for free, with predrilled holes! The amount of work to drop the headliner, weld them up, and repaint is the only thing keeping it on there.
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