I finally got around to replacing the heater box. 7 hours later, everything seems fine. My heat is hotter than it was before and the AC is nice and cold.
I did end up breaking the trim piece that holds the clock...Anyone know where I could pick one up? Ebay has them for about $90 including the clock (my clock doesn't work so that may not be a bad option). Anyone on here have a parts vehicle to sell from? I have a black dash.