yep that's why i am buying a TRD
knob to screw on...but anyway, that knob goes on the same was as a Momo.
It should have a rubber fitting thought that would be placed over top on the top of the shift rod. Then the shift knob shouold fit over that so it stays on...no wiggling. THe small screw is to hold it like a Momo...it just screws and holds itself on the shift rod...my momo comes loose sometimes but it is pretty tight...you can't be that aggressive with it.