Heater core replacement

Hey guys
I know I'm kinda sidestepping into enemy territory here, but I'm trying to help out a buddy of mine.
He's got an '88 5.0 and just replaced the heater core. Now, He's got some lines to connect and can't remember where they go. There's 2 lines (Left and Right) coming into the engine bay through the firewall that go into to fittings (Top and Bottom) on the engine.
Which one mates to which?
Thanks alot in advance!

Are they the heater hoses? The lines from the heater core to the water pump? If so it doesnt matter.

yea if they are hoses than what ever fits, but he has to either find or fabricate a flow restrictor for the hose that leads to the heater core. not having one is the a major flaw and leads to premature leakage!
http://home.netcom.com/~skent/mustang/1990/heater_core/hcore.html

and drop the enemy territory stuff, no one cares but you. :cwm27:

Take a read though my write up, you might be able to find something useful.
http://www.dork.com/hiflow50/heatercore_replacement.html

Guys, I appreciate the input and will pass it on.
Thanks alot!

As a general rule of thumb, it's advisable to use the pipe that is at the bottom of the heater core (as it's installed in the vehicle) as the inlet. Unless the pipes are different sizes of course. This allows any air in the system to escape the core and prevents the gurgling sound heard in some cars. Just a tip.