Why not just cut the chain so it just clears the rear derailleur pulleys/cage in the small cog/small chainring combination? You can use (just about) any size casette/freewheel; no problems, no adding or cutting links. By having the chain long by some standards you- put less stress on the derailleur spring(s)-enhancing its/their lifetime and reduce friction- negating the negative effects of any excess weight ( "Eddy B." - Bicycle Racing) among others.
With the tight-ratio clusters Eddy B's proteges used, that works.
With wide-range gearing, however, this can lead to damage if the rider accidentally shifts into the large/large gear. Large/large is the critical case.
See also my
Derailer Adjustment article.
All the best,
Sheldon "Derailer" Brown
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| For every complex problem, there is a solution |
| that is simple, neat, and wrong. |
| --H. L. Mencken |
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