I hate to seem picky but you folks do realize I suppose the definitaion of a MonoBlock is not a short section of bbls, But a breech piece for bbls machined from "ONE" solid piece of steel. Cutting the bbls off does NOT convert the breech section to a monoblock, just bbl stubs.
Either can have tubes inserted to complete a bbl set, but if the stub has joints in it it Ain't No Monoblock.

Miller/TN
I Didn't Say Everything I Said, Yogi Berra