Shower is set up to Drain into Bilge (YUCK)

[cal 39 guy]

Im wondering the best way to set up my shower water drain so that water doesn't drain to bilge. I know they have the rule shower units, but i don't think that it will fit under my drain. I also have a pump that i think can run dry.
the inspection hole picture is what is below drain.
2nd pic is shower drain. the underside of drain doesn't seem to have a barb for a hose.