The original idea is simple and symmetric, two crates on top and two on the bottom. During our visit in Jan 2024 we looked at these spaces, and found that the spaces under the magnet were cramped, dark and hard to get into (likely needing confined space designation). | 
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Plan B was to place all 4 racks on top. However, for the bottom crates, this adds a lot to the fiber length, see here | 
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For the A-side bottom panels, here is a possible closer location. Looking with this viewer from 20xx, We are on an A-side platform, you can see the downstream lower coil. The fiber bundles (red) come around almost horizontally, a very short run. | 
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On the C side, looking downstream along the magnet iron. There is much less space there, but the platform dead-ends there, and our rack is small... | 
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| During the Feb 2025 visit, it became clear that the placement of the crates servicing the bottom panels on the sides was very problematic, and we went back to looking at the spaces under the magnet. This picture shows the access to the space on the A-side. The pipes and hoses should be rerouted to make entry a little easier.
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| After entry in the passageway, there is a pocket on the left. The lower-C-side crate can be placed on the bottom of the magnet iron. A floor needs to be installed to make work in the area easier. The height from this floor to the magnet is 133 cm, the width is ~140cm.
We also need a few steps to get up to this level, which is 90cm above the cave floor, like these:
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| While looking for drawings of this space, I found that this yellow
steel is missing from the big hall STEP file (LHCb_full2.stp)
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