I made one a coupke years back for my 2005 Shadowcat. Mine cost me nothing as I already had some old parts laying in a drawer.
It's fairly simple really. All you need is a doglegged cable rod (aluminum) and the rubber bumper. You have to experiment a bit to get the length of the rod correct then cut it to length. Install the rubber bumper and install it in the hole on the back of the riser. Tighten the set screws and you're ready to go.
Cost for the whole thing would be about $13 to $15 if you have to buy the rod and bumber. Martin sells one for about $20 so for the hassle you'd be as well off to just buy theirs. Check the on-line store.
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