I would drop in some Bar's Leaks pellets before tearing into any heater core in a vehicle built after 1995 or so... I've heard horror stories of hours and hours of work and entire dashboards having to be torn apart. I know lots of folks scoff at the Bars Leaks pellets but I've had excellent luck with them and it's saved me tons of headaches and money. Seems to be basically a permanent thing and I've never had any reduction in heater output or cooling efficiency. I've got that stuff still working in one of the cars and it's been over 5 years now. I put some in everything because it's got conditioners in for the coolant as well, and having that small stuff constantly floating around ready to plug a leak is priceless to me. Whatever the case, I wish you luck with your heater core problem.
On a separate note, we've got several new inches of the devil's cocaine on the ground. The ground is officially covered and I'm officially puckered up about it. I hate it here.
Just 5 more years, if nothing major goes wrong in our lives, and we'll be able to move the hell outta here and get south of the Mason Dixon to one of the "racist, dumb, deplorable" free states. My kind of folks! If the media knocks them, I'm gonna like them.