I was recently talking to Dale Geddes who has alot of
experience working on cars.
When he pulls the cylinder head of a Volvo 240/740, after unbolting the
intake manifold, he would move the intake manifold out of the way and tie the intake manifold to the open bonnet so that he does not have to remove all the other pipes and wires attached to the intake manifold.
When the cylinder head is reassembled back to the engine, precious time is
saved as most of the pipes and wires are already attached to the intake
manifold.
This time saving tip can be applied to various other cars, but not all cars.