I took the 727 Transmission (circa 1975) out with the motor. I know the transmission would move forward and reverse without hesitation but I could not check the upshifts as the car was not roadworthy. The transmission fluid was red and did not smell burned, however the pan had a lot of sludge in it. I ran a magnet thru the sludge and did not pickup any metal, so my first impression is that the Trans will be OK. I plan to flush out the trans and the convertor, replace the filter and gasket and put it back in... Is there any harm in hooking up air pressure to the cooling line inlet to the trans to flush out the old fluid and does it matter which line is the inlet and which is the outlet when flushing? Are there any bench tests that I can run to make sure the trans is OK before I put it back in?