I believe small block Ford V-8s like the 260, 289 and 302 use a 157 tooth with a 10-1/2" clutch.
PANTERA INTERNATIONAL
A DE TOMASO CAR CLUB
Presents the De Tomaso Forums
The On-Line Meeting Place for De Tomaso Owners and Enthusiasts From Around the World
Clicking on the banner will take you to the sponsor's website.