Does anyone know how to access the step down bilge pump for the Head/shower enclosure on a 37 Outerlimits?

Not sure what you mean, you lift up the step on mine and the pump is right there.

Depends if your boat is side by side seating or not, if you cabin door is offset the way mine was with side by side seating. They had a pump under the sink in the bathroom and there was a hose that went to the floor and with a float to turn it on.

sawzall lol

Yes mine is side by side with the cabin door off to the left,my pump is running but not pumping ---sounds like its mounted under the raised area the head is mounted to ----I might need to cut an inspection hole and put a hinged hatch.