With a gut/cord, tie a knot in one end. Put the cord through one hole in the base of the tailpiece, loop around the endpin, and put the cord back through the other hole at the end of the tailpiece. Tie a knot in that end.

Easier if you test fit it, remove the tailpiece after determining where the knot should be, and giving yourself some slack to work with. The end of the tailpiece should be about over the saddle- the critical distance is the "after length" of the strings , between the bridge and the tailpiece. Changing this WILL change the tone of your instrument.


Modern 'nylon" tail guts are threaded, but the principle is the same.