My early Citori has an action like the one shown in the spring making video but it definitely has COIL springs. I think that at some point Miroku adopted the Niettner system and went over to coil springs working vertically in the action recesses.

Perhaps it is worth making sure whether the springs are coil or V. Coil springs on my Citori are dead easy to remove and replace. Easier than behind-the-hammer type of spring.