I just got hold of a standard Fender Jaguar preamp used in their CIJ models. The body I'm putting it into was already routed for an 18v double battery box. I had planned on putting and Aggie preamp in there at some point, but got this Fender preamp and pups cheap and so it goes in. Can these Fender preamps take 18v? Any benefit from the added power? Thanks!