I have one, but have never let it run through the gears with a heavy foot while manually locked. I'm guessing that even with my good V/B and T/C, the shafts and flex plate won't appreciate the slam of the shifts.

 

now can this be done on a 99 24v?! read somewhere that it only works on 1st gen or early 2nd gen trucks.... looking to get a TQ lockup for mine becuz it will DRASTICALLY help with driving and help a whole lot at the dragstrip

 

as far as i know you can't.