Help please,throttle lever

can anyone give me some advice,the throttle lever on my 904 tranny is stuck in position,it is all the back towards the rear of the car. it won't seem to move no matter what position the shifter is in.i have installed a new 408 stroker motor and a shift kit in the trans.while installing a new b&m floor shifter i discovered the throttle lever will not move.thanks in advance for any advice on wat to try next...........ROB