by "my shifter is bad" do you mean its sloppy? or is it grinding or what? try to be a bit more specific. if its shifting sloppy, try looking up BillyM's bushing kit. from what i read on here, its quite easy to do yourself, and really makes a difference in the tightness of your gear pattern
If you put your shifter into any gear and have more than 1/2" of movement side to side, you have a damaged shift socket, and it can cause all sorts of problems from slop to increasing difficulty in shifting into 3rd primarially and then other gears following.
A short shifter will not resolve the underlying issue, and you will have to either replace the shift socket with factory parts ($150+drop/split the trans) or a socket repair and bushing kit (such as what I sell), same result just two ways of getting it.