Need to change a heater core in a 99 marquis, what do i have to look forward to?

I have a 1989 mgm and i had to replace the core.The heater core is in the passenger side on the bottom ofdash board. All you have to do is follow the 2 heater hose that go to the firewall from the engine.It is about a 4 to 7 hour job it depends how firmiliar you are. I would do some researchfirst to make myself firmiliar before i would attack it.It isa square boxin the bottom of the dash board on the passenger side.Good luck[img]smileys/smiley3.gif[/img] Edited by: pdman