i know people with good experiences with cheapo kits, so long as the mechanism is smooth and isnt 'rough'.I never installed one in my car so I don't know which ones are good. But I've heard of ones that just move the fulcrum points. How it moves and how the short shifter does it is the key point.
just make sure theres no play and you should be fine.... option b, is to cut and weld (or in some cases its just a matter of adding washers), also know ppl who have done this but you got to get it right in one go otherwise u end up with a horrid throw