heater core question

So couple months ago my heater core went out (leaking inside car), i bypassed it temporarily. Yesterday went to the local junk yard and pulled one off a 2002 galant get home and upon doinf more reading up on it the hc is differant from 2001 to 2002, i have a 2001 is there a way to make this one work or am i just screwed till i exchange it? Btw the jy is 40 miles from me, what should i do i havent torn into my g yet was planning on doing it today bc i have to go back to work tomorrow.

The only insight I can share is that the 99-01 is different from 02-03, but it seems you're already finding that out.

Yeah lol its the way it goes right