Ok, hope this helps put a little light on the issue. I had a tremic 3650 in my 08 gt. I too after modding the car and shifting at higher rpms would get blocked out of 2nd gear and sometimes 3rd. (stroked,blown,4.30 gears) ok, tried the hurst shifter with che tq limiters, helped the issue greatly but here is where the story ties into what I think you may end up stumbling apon. After being "fixed" it ended up doing the same thing again, so I bought a STOCK NEW 6060, and that for a while (short time 1000 miles maybe) and it started blocking me and grinding while torque up in a hard pull and at high rpms. SO, call around get some quotes (t56) wasn't out yet so I sent my 6060 to liberty gears. They went through it, upgraded everything and did the cryo treatment. SOme odd dollars later I had a car that shifts like butter. NOT EVEN A HINT of anything stopping me from going into gear. I hope you really have a fix and not a band aid but in my case it was a band aid. Good luck and keep us posted on your progress.