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I am having difficulty picturing what you mean about the bar that is attached to the chassis at its front and to the cable at its rear. I do not have C10 (other than Blazers, as such), and those emergency brake setups might be differently arranged than the pickup. It is cold out there tonight or I would go look for your sake.

However, my basic memory of these setups on most or all of the these trucks I have worked upon is that the front cable (from the pedal mechanism) has a threaded rod at its back end, and that this rod goes through a "V" shaped flange of some sort, backed up by an adjusting nut (for cable length/tension). In some manner, the cable arrangements to the rear brake units are attached to both tips of the 'V" piece, or maybe actually it is a one piece cable that rides in a groove in the "V" shaped flange and goes out to both brake units.

There may be a guide piece or some other attachment to that front cable - up toward the front of the cab - to keep the cable in place and direction - but am not certain of that.

If you do not get a useful answer here by tomorrow eveneing, I will have looked at one of the Blazers and at a C20 and should be able to tell you something definitive at that time.

Good luck.
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