Heater hoses
 

Hello,

I'm trying to replace the heater hoses on my 1966 Chevy C10. It has a straight six, I believe a 250, but I'm not sure.

At the water pump end it appears that one of the stubs is 3/4" and the other is 5/8". At the heater core end it appears that both are 3/4". Is this normal? Am I supposed to use an adapter or just force the 5/8" end hose on?

When I realized that the hoses were different sizes, I figured that I didn't need to pay much attention to which hose was which, since it appeared that there was no way I could get them backwards. Which way do they connect? Will it hurt anything if I have the water going trhough the heater core backwards?

Thanks,
Eric