There are 2 different sized BSC1 if I'm not mistaken.
The very first ones had the 2 switches on them (a pad and bass roll off) which the subsequent ones did not.
A friend had the early model with the switches and I have the model without and I'm pretty sure the earlier version was slightly bigger.
As I say, I could be wrong but I'm pretty sure that's the case.
Not sure how much of an issue that could be, just wanted to throw it out there in case it may matter...