First of all, is there any way to move the crankset inboard, ie is there enough chainstay clearance?
Then, the question of derailleur swing can often be worked around if you have a band mount FD. Manufacturers use the identical FD geometry an all their band mount FDs (of the same model range), so the smaller the seat tube diameter the shorter the outboard reach of the FD. (This is the real reason Campagnolo discontinued 1-1/8" clamp Record FDs). So if you have a small seat tube, you can increase the outboard travel by using a larger clamp derailleur and a shim.
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Chain-L site
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