Looking for some advice from some luthiers here. Today I got to look at a bass that I previously detailed here as having about ten cracks (all repaired). The bass plays and sounds very good and all the cracks seem well repaired (except one - see below) and stable. My two concerns: a) There is a reasonable amount of sinkage in the top - more on the bass side than the the treble side. My current bass has sinkage too - this bass has more - and mine is not not uneven like this one. In both cases I believe the sinkage has occurred quite a long time ago. b) The bigger problem is that one of the cracks is in the heel of the pegbox (if that's the correct terminology). I'm talking about the heel of the neck where it joins the pegbox, not where it joins the body of the bass (I've seen this called the root at times but also the heel). That crack is still a little open and basically it appears it was repaired by putting two screws through the fingerboard. The heads of the screws are visible but flush (just) with the fingerboard. Of course this is right up towards the top of the fingerboard. It seems stable and doesn't affect the playability but it definitely looks a bit messy there. My uneducated guess is that if the fingerboard were to be replaced that this repair could be done properly with the crack closed up fully and the screws or whatever put in behind the fingerboard. The neck is quite thick BTW. I am guessing that such a repair wouldn't cost too much to do. I am wondering also whether a C extension would be a good thing since it would put some pressure against the scroll to act as a counteractive force to the forward pulling pressure of the strings. Or is that just wishful thinking (I must admit I haven't thought about it much)?