it would fit the gt shifter
yup, both the gt and gts use 1/4" threads. however, it wouldn't make sense for a gt to get it because the gts shift knob has the gear settings different (the reverse is opposite..plus it has a 6th gear).
so unless you plan on shaving the top of the leather off (why someone would do that i don't know)...it wouldn't look right purely from a style and function point of view.