Wanted: Torque wrench for cranks and what tension for Sugino 75

To find out the correct torque for the different parts, would I just have to nip over to the companies websites etc?

A lot of that old stuff pre-dates the notion of scientific spannering, so you'd have to sit down with a pencil and paper and carefully think about what would be an appropriate torque. Look at modern kit and see what torque is used on similar thread sizes as a starting point, and learn about the relationship between torque, which you apply to the fastener head, and tension, which is what the fastener shank undergoes and transmits to the component as a thrust. You should actually work backwards from the desired tension to derive the required torque.