Panterapatt is correct, the Alfas use different length cylinders. Long thread last year on this very topic (Clutch Slave Cylinder - Leaking Again | The De Tomaso Forums (infopop.cc)) I show measurements/photos of both the 105 and Pantera clutch slave cylinder and they are different depths. I own both a Pantera and Alfa 105 so I had examples to look at directly. The Montreal cylinder may be longer than the 105 version, but I still believe both are shorter than the Pantera version. I ended up having White Post restorations rebuild my Pantera version.
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