Clasp nut modification

As standard, the Myford has its clasp nut release in the form of a lever on the left hand side of the carriage handwheel. I have heard a number of folk suggest that it would be better off on the right-hand side as I believe is more common on American lathes.

Well, my lathe has been modified sometime in the past by the addition of another lever, connected to the first. The pictures below will make this more clear. So far, I have not been able to find out if this isa one-off user modification or whether is is based on some published work.