in addition that small pedal that jim refers to might be gone and in its place a spring located under the foot board holding that shaft in position. If the spring has come loose the pump has disengaged.
as far as re-routing the loader/backhoe hyd to the pwr steering consider the following: the internal hyd system is a 1150 psi open center system. is the external system open or closed center? priority and flow control could be a challenge.
also the filter jim referred to is a metal screen mesh filter that can become clogged. try cleaning it in solvent and re-install. a new one from deere is around 150 bucks.