Heater core question

[The Frisian outlaw]

Hello you folks.

I just got my new heater core from The States but I forgot 1 thing by disassamble the old one...... . There are 2 pipes with different diametres. My question about this is:,, Which one must be on top and which one down below?". The widest pipe on top?

They've cut off the heater core more than 10 years ago, so there are no hoses to fit on the heater-core pipes, that's wy I don't have any clue. There's also not a picture in my manual, only the one with AC and mine is without.

Thanks,
The Frisian outlaw

[vectorit]

Larger pipe on top connects to the water pump connection.
Smaller pipe on bottom connects to intake manifold connection.

[The Frisian outlaw]

Thanks for the fast reply!

The Frisian outlaw