Those numbers have been rounded, the original dimensions are listed on the back of the flyer as:
Height: 54.25" (137.79cm)
Width: 20.44" (51.91cm)
Depth: 23.75" (60.32cm)
Weight:185 lbs (83.9kg)
15" Quadrascan Monitor
Basic dimensions are commonly listed on the flyers, and occasionally you'll get a usable line drawing you can use so they're generally worth checking when researching projects like this one.
TAFA is a KLOV like repository of arcade flyers and a great resource.
The Battlezone cabaret used the same cabinet, so reference pictures of it would be usable as well.
Here are a few.
KLOV has a operator's manual for the Asteroids Deluxe Cabaret available, which has parts diagrams that should be helpful.
A cabaret will take less material to build, though I woundn't go as far as saying building one would be any easier than a full upright. It'd be the same amount of work, though there are some different challenges involved.