Need Size on A/C Evaporator drain hose 94 pkup

Hey guys I had water leaking all over my passenger floor board, I traced it down to the plastic nipple on back of the evaporator housing. Directly across from it is a hole into the firewall with a grommet around it. There is no hose going from the nipple to outside the firewall to drain the water so its just dripping down the firewall onto my floor board on the passenger side. Does anyone know the part # or size of oem hose that is suppose to be used for that ?