How to fix sill extensions

Just wondering how the sill extensions are mounted on a s1 exige.

I can understand the top as they are bolted into the chassis with m8 allen key bolts, but how are the bottom ones fitted, ive heard some people mention pop rivets, others stikaflex.

Just wondering how they are done on the factory vehicle, i looked on the workshop manual but couldnt find any info on it.

thanks in advance

The bottom is simply held on by two push fit plastic fasteners.

are there holes in the chassis to take them or do you need to drill them, when you say push fit plastic, are we talking to same type that hold the plastic gearstick surround on?

The plastic clips to hold the bottom, go into two holes in the fibreglass sill.

As you have said the top is held by two bolts that go into captive nuts in the top of the fibreglass sill

well one of my captive nuts is buggered and pushed through into the chassis so im going to use rubber rivnut to replace it.

I was also thinking of using them on the underside for the sill extensions and they are meant to be good for joining panels together.

What type did you use?

Looked at the exige parts manual and looks to be the cheap plastic ones,

Cheap plastic ones are good, as if you catch the sill extension on anything, it will simply break the cheap plastic clip off and not rip a massive hole in your sill.