Heaviest gauge on Schecter Stiletto Stealth 5 string

[DECEMBER]

Hello,
I'm wondering what's the heaviest gauge string anyone's fit into the nut on a Schecter Stiletto Stealth 5 string bass without having to file out the nut.
I'm just interested in the low B string space. I want to drop it to A and the Kalium string tension calculator shows a .148 at A has the same tension as .130 at B.
A .125 didn't fit in the nut on my 4 string, so I'm wondering how big I can fit in the Schecter 5, as close to .148 as possible.
Thank you

 

[DECEMBER]

Wow, nevermind, this thing sounds like crap! And FedEx obviously dropped it pretty hard, chips in the side of the neck. The A and D strings have terrible fret buzz and when finger plucked, sound like an upright bass.
It distorts really easy, on the high strings. I have an Ashdown 220W 12" combo with separate inputs for active and passive.