You really do not even have to do a real spread of the frame to go from 126 to 130. The real way is to cold-set it. Pretty easy to do, or have done. But, with only a 4mm difference, you could just spring the stays out with your hands when you are installing the wheel. Not trying to talk you into going to more than 7 speeds, but just saying it is easy to do if you wanted.
jim
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