So here is how it was done... Note that my Mini has an engine conversion, aftermarket seats, and many other internal & external modifications so I had no qualms in performing a small modification like this.
I made a cut using a thin kerf disc on the grinder to remove the bin. You can see here I tried to removed the spot welds on the B-pillar but I couldn't get access to them all so I ended up simply cutting the rest of the bin out - at the base and along the B-pillar
A couple of small welds against the B-pillar were removed using a die grinder
After cleaning up pieces of steel still attached to the body, I marked the position of the new inertia seatbelt reels and found I had to remove more steel
I wanted to retain the finishing trim strip that clips on top of the storage bin sides. This was done by taping a few pieces of 2.5mm steel to my vice and clamping the new steel sheet between them in the vice. By repeating this along the length of the steel sheet, I ended up with a pretty close approximation of the original lip on the storage bin edges
After trimming the bin-front to retain only the curved section and to the match the floorpan shape shape, I welded on the new steel piece.
Using butt welding clamps (I love these) etc, everything was held in place and welded in.
You could leave it here but I wanted to make a cover for the seat belt reels. This was a box made from 0.8mm steel sheet that was a snug fit over the seatbelt reel. Overall I achieved an extra 40mm of room per side of the cabin. Note : I hadn't yet drilled the holes for the mounting screws in these photos.
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-Alan
I blame my dad for my love of minis. I think I was conceived in the back seat of one
I also blame my Dad for me being 6' 1" - not really the optimum height for driving a Mini.