So this is the mechbay I’m building.  Eight stories underground to the bottom.  The deck height is to Moonbase scale.
The base started as a regular Moonbase two plates wide; but then I wanted a storage area under the mech main level, 
how ever that pushed the main level up a few stories.  A mech would have to walk up a ram or use a lift of some kind.
Moving storage area underground didn’t work for me so the whole thing went down under.   

Using Moonbase scale the 2 plate wide limited me to just 4 studs wide between the front and back of the main lift and 
the outer walls so what I thought would be a simple redesign turn into major work.  The challenge was the pillars in the
lowest level and I had started on the next level up.  I went from two 48X48 base plates to six 32X32 base plate in 
a 3 by 2 configuration.  No longer Moonbase scale, but I am very happy with the increased room and the new pillar design.

Still lots of work and I hope to build it in real life one day, and it will definitely be a big SHIP

Question/comments: third0481@gmail.com