Sill Closers and Oil Pipes
The 2.2 wouldn't have had sill closers to the front originally, but they are a no-brainer. They help keep the road muck out of the sills, fully box them and are hardly visible when the car is built.
The 2.2S is complicated of course by having those oil pipes, so there has to be a compromise on the sill closer to this side. Even so, it can't help but stiffen the whole structure up.
To the rear, a kidney bowl has to be modified to allow the oil pipes through. I put a tiny flare on the top of the metal, so a) there's no chance of it fretting the pipes, and b) it gives somewhere for the bead of sealant to sit neatly.
With the oil pipes, kidney bowls, jacking points and reinforcements plus those closers all in place, the outer sills could be welded in.