Another thing on this... (Sorry again for the tread jack, Manny)
If you look at the detail drawing for the component breakdown, parts 50 and 51 are actual structural components... as are 3, 4, 5...
The guys praise the need for ttops, but knowing just how "flexible" g-bodies can be, I would stay away from a T-Top car, unless it already has a cage (shameless plug for Koa's car... )
Astroroof cars do have more structural bracing under the roof panel, as well as the reinforced foor for the glass top... too bad Monte SS' never came with the astroroof option...