67 Dart heater core removal

Thanks for the replies. replaced it 20 years ago when I first got the car and started restoring it. Had to remove dash assy for window opening rust repair and did it at that time. need to take it from Arkansas to lower Louisiana for work on next Tuesday so I guess another working weekend......Will not have time to order a gasket kit for it, so any suggestions for what to use for the seals and gaskets?

I used 1/8" closed cell foam rubber sheet. Worked really well