being that the bass uses a floating bridge, it isn't absolutely critical BUT do a mock build with the tail piece and tuners in place, the pick ups sitting in place and measure the scale ( 30 inch) from the back of the nut to where the bridge sits, as I said because you can move the bridge you should be able to set the neck to look neat and still be able to set the scale right.( use twine or fishing line instead of guitar strings) Also don't forget break angle needs to be set at the same time, again doing a mock up will show you where it needs to be.