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Just easy cruising, yes. If you have your foot in the pedal, no.



And the MOST adjusting of the shift points (via the throttle pressure linkage/lever) is when the lever is at the end of its travel when the throttle is wide open.
Once you've done that, the tranny will shift as late (higher RPM) that the lever will allow. To make further adjustments require internal mods/adjustments.
Simple as that.
Now you can drill a new hole in the lever (closer to its center-point) which will give more lever-travel per a given amount of travel of throttle. That will change the part throttle shifts but the wide open maximum adjustment available is still at the extreme travel of lever.