That's how it looks in my 1956 one.
13 mm deep at the neck pickup and 7.5mm deep on the bridge pickup at the short edges.
The bridge pickup cutout looks much different on the Newark St. model.
However on my one the bridge is pretty low and hence the bridge pickup as well. I guess the neck angle might be different on a Newark St. Aristocrat. (that's a compensated replacement bridge in the picture, I still have the original straight one, also it's an old picture when I got her, the pickup is fixed, so the pole pieces do not look out so much anymore.).
So I would simply cut it our like on the original version and lower it to the desired height, using shims on the two braces it can be set higher as well later on if needed.
Ralf