You might be able to use your current shafts. See if you can cut the back end off the shaft and then move the shafts back, thus shortening them. Whittmers Coach shop in Narvon, PA is the best for supplies. No website but they have a great catalog and are very helpful, you can call them and Mr. Whittmer will give you great advice on raising the seat and everything else. If you cut the back ends off your shafts you might be able to use the cut off part to put under the seat, on top of the shafts to raise the seat.
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