Doug's Headers A453 in 70 Duster with 4 Speed my experience
Mine slid in with the engine and trans on moving dollies (yes I play with dollies, I dress them up and we have tea like proper ladies) and the whole car 3 feet in the air. Car down, Engine/trans up. Done.....then put everything else back together.
I think people are not prepared for what cawcislo outlined nicely above. Slide or drop is subjective, like "low rust". Low rust to some people is just some daylight showing through the floor boards, and frame rails, and rear quarters.....