They all have the pipe, it’s for the heater which all models have. I usually just buy a new one when I change the pump.
As for the sizes, the hoses are both 5/8 on one end and 3/4 on the other. They are different so you don’t get them mixed up.
My guess is if you were able to use standard hosing, you probably have the flow reversed through the heater core meaning you likely have the two 5/8 ends connected together and the 3/4 ends connected together. I always buy molded heater hoses specific to the YJ and they are a perfect fit. The one other benefit to molded hose is that they have the built in 90° YJ specific bends which is nice. Other than that doesn’t really matter.
