bb 402 heater hose routing

[gmc 2500 4x4]

i have a bb 402 and the water pump nipple on top has short hose to intake, the nipple to left of that on intake goes to heater core i presume. hose coming from heater core goes to radiator or can it go back to the plugged nipple on water pump? (radiator has no inlet)

[geezer#99]

The short hose is the water pump bypass.
Other hoses just run from the intake to the bottom bung on the heater core and from the top of core back to the water pump.

[gmc 2500 4x4]

thats what i thought, need a nipple on pump. my books dont show correct routing, thank you!