Does anyone know if the shifter knob from a 90 samurai tintop is a screw on, or if it is glued on. Im having a hell of a time trying to get it off

Screwed on.  Or in polite circles, threaded. 

I destroyed one in order to find that answer...

It was on a '88 and I was going to swap a nice knob from a '90 with the engraved shift pattern when I chewed the '88 knob  up with adjustable pliers.

I believe they all are threaded.

any suggestions on how to get it off? i dont know if im just lacking the man strength or what.....maybe its locktited on?

I've used a pipe wrench with a cloth rag to try to stop the scratches. You can heat the shifter arm if you want but be carefull not to melt the knob.

thanks for the suggestion

Take your shifter out of the control tower, put the shifter in a vice(wrap a small shop rag around the stick to prevent the vice from gouging the paint/metal. Use a large pair of channel locks to un-thread the shift knob, if your going to reuse the knob, wrap the knob with a rag to prvent damage while removing it. Hope this helps you!