Absolute minimum gear necessary:
1 prussick
1 throw rope
2 caribeaners
There is no physical way of setting up a z-drag w/o this equipment.
If you don't have a prusik you can do a truckers hitch with a biner but you will reduce your ropes breaking strength because of the knot. Additionally you cannot adjust your anchor point without untensioning everything and unhooking to reposition.
Points of Attachment in the Z-Drag (3 Point System)
Anchor point 1 - The Boat (thread the rope through a binear)
Anchor Point 2 - The Tree "The Achor Point"
This is where you want your pulley and a prussick
Anchor Point 3 - A second Prussic with a minimum of 1 caribeaner
If the boater is conscious and able to make eye contact they may be able to help attach the rope to their boat (especially boats with anchor points near the cock-pit rim). If they are not able to help, you may have to try
and do this yourself if possible.