I left my shower connections alone but did something somilar to the above post.... I bring along a TEE water connection and a second clean water hose with a hose end water sprayer and hookup this up to the city water connection along with water hose to the trailer.
This is great having the second long water hose around to squirt kids, dogs, and squirlles with... I just hang the water sprayer on the edge of my fornt deck.
Roy Ken