Matty no you do not need to take the pan off. unhook it from the carb first. then unbolt it from the trans and use a pair of needle nose pliers to hold the wire coming outof the trans and unhook it from the cable. then route the new cable down and reverse the procedure you did to take it apart.
__________________
I Live my life in such a way that when my feet hit the floor in the morning...Satan shudders & says "Oh shit, he's awake!"