This is not a "simple" issue!
There were several variations of the clutch release mechanism used on those trucks.
In order to home in on exactly what you need, I need to know the "chassis number" of your vehicle. In later years that became the vin number but in this case refers to the actual chassis number stamped on the outside face of the driver side frame rail behind and to either the front or rear of the wheel/axle.
The "key" digit in the chassis number is the letter prefix. A somewhat different clutch release was used on vehicles built with a chassis number prefix below "h".
If you will provide your chassis number digit, I will make a .pdf of the appropriate parts list page and post here, then you tell me what part you need.
I have a similar vehicle coming here to binder u. On Sunday that is going to be parted out over time, it's a manual transmission vehicle and could very well have the part needed, if it does we can supply the used part.
