Keep in mind that you have another option.
You can use a RD only guide and route the FD wire under the BB, as it is on modern bikes. If you wish you can glue on a guide, or as we did BITD, just run the wire and let it find it's own path, then apply a strip of muffler tape where it rubs. On one of my old road bikes, I just laid the wire on the paint, and it took 5 years to wear through a few coats..
The only problem with DIY under the BB routing is that the wire won't be parallel with the rear one at the downtube.
However, I'm sure you'll find that you can make the current 626/a clamp work for you if you're a bit patient. The key is to clamp it as far down the tube as possible short of touching the lug, and not obsess over a bit of incidental rubbing (if you have any).
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FB
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