I have started on this, the body has been planed flat, the the 1/8" mahogany has been glued on the top. I routed a small chamber between the bridge and the bottom edge, and epoxied in several packages of lead fishing weights. Many years ago I scratch built an Explorer-style instrument, and balance was issue #1. Drilled holes in the backside and loaded with lead back then. This time you can't see it.. Also made the control cavity larger to fit the Audere preamp and the battery. Also made a slight body contour on the backside (I gained some weight over the years...lol..) One thing to note. although the EMG 40 is close, the Bartolini CF is an exact match size-wise. Got a set of Bart CFSJ's on special order, the only way you'll get'em. Also attached a thin mahogany veneer to the headstock. It's where I'm at this moment, I have pictures, but I need to figure out some things.. Be back..