The I&T manual has a paragraph on this adjustment:
Remove center panel from rear of steering column shroud. Adjust length of rod between foot pedal and pivot linkage to 129.5mm/5.1 inches. Adjust length of rod between pivot linkage and hydrostatic unit to 137mm/5.4 inches. Start engine and shift trans to low range. Adjust neutral rod spring tension nut to provide sufficient tension to return foot pedal to neutral position when released. Stop the engine and move the foot pedal to fully depressed position. Adjust length of pedal stop bolt to just contact step plate, then lengthen it two more turns.
There is picture that goes with this showing the linkage and numbering the parts for reference. If you need a scan of this page, just shoot me a PM.
Ed