Which master cylinder do you plan on using, and have you done your homework on the cylinder diameter and stroke, and the volume of fluid it displaces? If you get a mismatch between the master and slave cylinders your "safety" modification could turn a rig that big into a rolling deathtrap. I believe you'd be a lot better off rebuilding the original system to "as new" condition unless you've got the engineering and fabrication background to do it right the first time.
Jerry

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