I had a great little discussion here. Hit the damned "clear text" button instead of a decently visible "post" button. Dang it. You'll just have to guess how brilliant was my discussion.

Basically I would use carriage bolts on corner mounts, truly secure. While I would have no qualms using brass inserts, it is nothing to sit on a carriage bolt head. I like your seats, like the clamp system with more than one fastener per corner and the tilt up aspect.

But really, I swear...it was a brilliant and witty discussion before I hit that doggone clear button.