Drove to school and back, got gas, put in 15 gallons. Then I went home and warmed up my bottle of Lucas p/s stop leak so I could pour it in. I filled the reservoir from the point it didn't mark the dipstick, to the full hot line. Then I let it run for a bit and turned the wheel back and forth a few times to get it in the system.
Also either I made a mistake or something's up, my calculations were that I went 417 miles on the last tank of gas, I'll have to go out and check again because that has to be wrong, that would mean 27.8 mpg.