I would think that it would give a strong enough platform to just use the original method and screw in from the top. I don't believe the screws in that position are under much of a strain, and are more just there to hold it in place as most of the tension applied would be from the top where the strings are doing over it (and pushing down).
Well may be...... that is a good point about the strings will predominatly be applying pressure downward on the nut which is good
, but I have watched a locking nut baseplate rip out of the holes in the wood before as someone screwed it in. Also the dowel will be tiny. I have filled holes before slightly bigger using dowels and after a while the threads go again and your back to needing to fill the hole again. I've had this happen with old strats and their six trem pivot screws. I'd be worried that once redrilled, there literally will only be 1mm left of the dowel which would not be enough to hold.
I'm not over thinking I'm just being cautious, I personally don't know if 1mm (could be less or a bit more) of wood filling would be secure or not which is why I am asking. I knew that was a possible solution but I didn't know how possible, again which is why I'm asking.
The whole 1mm thing as I mentioned way back at the start is 1mm gap between the locking nut base and the fretboard which yes will mess up the intonation of the guitar. I never mentioned the height of the nut
(although if I get one of the replacements installed, the the wood will almost certainly have to be taken down because the replacements are thicker and I don't want stupidly high string height at the first fret)I have asked my luthier if this solution is viable.
In regards to drilling holes in from the back, in my experience I have had luthiers try and talk me out of things before and also try and push THEIR solutions onto me before, I've also had them ruin guitars on me, and then had to get another luthier fix them. So this is why I am thinking the way I am thinking. I could honesltly see a luthier just say "oh forget about the filling the old holes and drilling new ones, what about rear mounting bolts? This would save messing around with pluggin up holes". It would also be quicker to do the rear bolts thing as it's just straight forward drilling with a press and no plugging up anything.
But as you all know I would be keen to avoid this at all costs.