About positioning the plate, if you put the rim bolts in, all of them, but just an eighth inch from tight you will find there is almost no movement possible. That IS the plate position. The pinblock would then need to be fitted to that position. As for the horn wedge I am not surprised there is a larger gap. This is not unusual for a flexible plate like Masons used. After you have a few strings on and get a little tension on the plate you can then place the wedge in place and it will stick. How did you determine that the board lowered? This is possible but only if the strings were holding the board up above it's crown, if it has any at all. Have a careful look at that with a thread along the longest rib along the surface of the board, not the rib. That information may well determine your approach to the rebuild. As for the scaling, see my earlier post about this subject. As for the bass strings, those will be on a scale stick at the string makers or it can be rescaled from scratch with just he speaking lengths. You have a good project on hand there. Newton
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