UPDATE: Tried "head gasket sealant" ($10 bottle from Advance). Basically said to drain and flush all coolant, and then run this stuff mixed with straight water for an hour or so and then let it sit overnight to cure. Ran for about 5 minutes on said mixture, then cut off abruptly. Pulled spark plugs and turned engine over, huge jet of water shot out of far left cylinder.

MORAL: DO NOT BUY THIS SHIT. IT NOT ONLY FAILS, BUT IN THIS CASE MADE IT 10X WORSE.

And thus . . . I buy a new full gasket set and rebuild this hoe. Can't complain for a $100 car.