We want to complete the loft in our 3 sided log cabin. It has a full center beam but we need to add cross beams and then the tongue and groove. What is the best and easiest way to cut into the log walls to create the ”pocket” for the cross beam log? How deep should the ”pockets” be (the walls are 8” 3 sided logs) and do they need to be attached with log screws? Also, should we start with another cross beam right next to the one that is currently the edge of the loft or should we give it som