Rear seat belt replacement?

[SeanH]

I've had a quick look on here but couldn't find anything.
The MOT is now overdue and the seat belts that the dog ate a few years ago must now be replaced. The only reason I've not done it yet is due to a very nice MOT tester that no longer works there!
Has anyone already done this?
How do I get to the inertia reels in the walls?

[SeanH]

Don't panic!

I set out to do it thinking it was going to be a complete ball ache .... turns out it was a piece of cake, 15 minutes and both were swapped over.