Yes the turbo shift shift knobs do have 6 gears on them. I wouldnt be that stupid to stick a 6spd knob a 5spd. Toyota had to make a FIVE speed shift knob for the n/a model. So anybody have something useful to say now that we got that out of the way?
it's gonna be pretty hard to find. watson sells it for eighty something. you might as well try to find something aftermarket w/ a similar color (hard for burgandy AFAIK, if anyone sees one let me know) for 60 or so.
Chris Jensen has had the MkIV 5 speed shift knob in his 89T since before I met him in 1997. It looks good... but he had to add something under the shift boot to bring the height up to meet the new knob - new knob is not as deep as the MkIII knob.