Hello! I'm thinking of ordering a UNI 4 preamp for my 2016 Fender Deluxe Jazz V. Will this fit without routing? I was thinking about the Retro, but I prefer the frequency & passive options of the UNI-4. Has anyone run into trouble fitting the UNI into a Jazz cavity? Also, is it safe to assume the UNI-4 run at 18v? Thank you!