the shifter thing(idk the name of it)broke off my friend ran over something...can it be changed with out pulling the transmission or would it be easier to weld something on to the broken piece to make it work

 

It sounds as though you have broken the arm of the shifting mechanism. The tech manual only addresses it after the transmission has been removed. I would recommend finding a donor trans in a salvage yard and attempt removing it. If it can be removed with the transmission in place then you can duplicate the effort at home.
You might want to try to locate a JATCO tech manual to determine the necessary removal procedures.

 

If you have both pieces still, possibly you could make a small plate (or 'gusset') and drill, tap and bolt it back together, as it sits in place, on the car.

Such a fix would likely even be stronger than the original part.

If you throw heat on that to weld or braze it, you run the risk of destroying the seal and maybe any internal soft parts that are near the shaft.