The tool for tightening the cotter pin types consists of a partially flattened tube with a t-handle welded to one end. I had one when I worked in a Fiat dealership, many moons ago. The hex-headed ones used on the 750 cars are much nicer, IMHO, not least of all because they can be tightened with a normal socket.
The only drawback of these clamps, for our Giuliettas, is that they should not be reused, though the pin and clasp can be recycled for use with fresh banding.
The perfect is the enemy of the good. Voltaire