I have decided to go with an OBP-1 for the project I bought this for. Included in the box is the preamp module and stacked pot neither of which have ever seen a soldering iron.
I'll sell the above for $100 shipped
For a little more (basically just the cost of materials) I will configure it any way you like with vol/vol, vol/blend, stacked B/T or not, with or without passive tone. All you would have to do in this case is connect it to your pickups when it arrives.