yep, both
tilt the tripod so the camera points-up enough for the building, tree, telephone pole, tall person &c to be in-frame ... then "level" out the front + back standards ..
its as simple as using front rise or back fall ... and not confusing at all ...
front and back just have to be parallel and its ez to do, and show even with
a box with a cheap lens and frame with waxed paper in it ( camera obscura ) what
converging lines &c do ... after all a bellows/view camera is just a type of camera obscura you put film in..
using a speeder or box camera would eliminate the need of anything film holder + exposure button ..