I am attempting to fix my heat problems on my 2001 Chevrolet 2500HD, if have narrowed it down to I need a new heater core. I have completely dismantled the dash to where I can see the top of the heater core. (probably should have come for help before going this far, but I figured this is how to get the heater core out.) Now I am at a loss I can see that it appears that it should come out the top, but I will have to bend the pipes that go through the firewall. Any suggestions or ideas on where to find out some better directions.