I still think your converter isn't locking.
I do as well. Seems like ben's box only works on the low RPM range. Seems like the ML converter locks pretty softly in my case. Definately not a 1058 or Junkstar :angel:
have you tried replacing the fuel pedal/steering wheel/brake pedal interlink logic unit with one that works? Yours sounds defective
Driver mod did not help either.