
Open, showing slides. They are fastened underneath onto the part that slides out.

Closeup of slide.
Looking at it again, it may have been replaced by a previous owner. You can see a cutout in the first photo that may have held the factory hardware.
On the forward end of the sliding part is a barrel bolt that fits into a hole in the forward bulkhead. On the aft end is a leg that folds down to support that end.
Hope this helps. Let me know if you have questions.