So I'm pulling the seized 400 out of my Cordoba for a running one, but what is the best way to deal with the torque converter to flexplate bolts being that I can't spin the engine to get to them? Would it be safer to take the engine and trans out as a unit so I can guide them apart easier as to not damage the front pump?

 

As long as it is supported you will not damage the pump The Cordoba should have lots of room to move the engine forward to disengage the converter. Personally I would remove it as a unit. Not that much more work. While it is out re seal the trans before installing it. If you leave the trans make sure to support it and raise the front of it uo as high as the firewall will allow