Don, I have a truck pan from an 83 Ram slant 6. The dipstick
tube just slides in and out of the pan and is held in place by a bracket that bolts to the motor mount. The hole in the block for a 'pasenger car' tube has a small aluminum plug tapped into it. If you look at this pic, you can see a 'dimple' in the edge of the pan, where the gasket goes, that shows where the block mounted dipstick tube would be. I don't think the block mounted dipstick will work with that pan. If you find a truck in a salvage yard, you should be able to get the tube out by just unbolting it from the engine mount and pulling.
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