help getting heat with a seized compressor

So, I'm about to drive the 80 from SF to Cleveland in my 1985 300ZX non-turbo manual digital dash, I have the digital climate too control and I don't really understand how to use it, and my compressor died a couple weeks ago and I don't have the money to fix it.

Previously in this car, if I needed heat, there are 4 options: AC, Econo, Demist, Defrost. Maybe Econo doesn't run the compressor? Since my car stalled out on a highway with smoke coming out the front as I pulled over, and I investigated and discovered that bearings or something had been shredded inside there and molten little scraps of them were oozing out the front of the compressor around the clutch, I haven't tried to run any kind of heat, just let it seep in slowly as it does with the blower off but the heat set to a higher temperature than ambient. But with the sub-freezing forecast across the upper plains and midwest, I'm worried the car will get too cold for travel.

Any help appreciated.