That baby is HUGE!
Don't rush that cure job on the silicone, even after it's stiff to the touch I have heard some nasty stories of people putting water in too soon and bam killing off a bunch of stuff, because even though while it's physically cured chemically it's still working some magic.
So ya got an empty glass box...
Ha ha ha ha ha....... After it gets in, the set up will go rather quickly ....
Ha ha ha ha ha.
Good joke.