Perrin short shift adapter shortened my throw dramatically. It is easy to take an adjustable wrench and just bend the metal plate up. The only drawback I see at all is the shifter knob height is exactly the same. I bought it directly from perrin so instructions are great.
--Stupidly I have also tried the agency short shifter. Throw is barely shortened. It doesn't seem one inch lower as stated. In addition, Agency or vivid never sends any instructions with their products that I have seen.
--I still have the agency shifter bushings sitting in my room. I hope to put them on soon. But, will they let me down also?