How do I release my Corsa rear seat locks?

The rear seat in my 04, 5-door, Corsa has jammed. I was returning it to its upright position, but on the nearside, the metal "bar" has gone in about 3/4 of the way, and on the offside, it has gone in even less. The seat is now stuck in an unuseable position, and it would appear that one/both of the locks has jammed. If I could find an "exploded" diagram, I reckon that I could replace the necessary lock(s) myself. Any ideas, please? Thank you.