I know this puzzle involves one of four things.

--The Monolith suspended 2 north of our current position.
--The Welded Gate, which blocked the plasma ball which is north, West, West of our current position.
--The Lever behind the sticky bars, which is West, South of our current position.
--The Furnace Room south of our current position.

umm...

SAVE GAME



Turn Dial West
Go: West
Go: South
Assemble Ballista
Use Ballista to shoot an arrow at the lever, thusly flipping it.

...I hope that works.