Anywaaay.. I've massively over cooked the depth of the recesses for the bridge units.. I screwed them in etc etc, put the strings on, and find they now slap about on the fretboard even when raising the saddles
The saddles themselves don't have that much movement upwards before you run out of thread on the l'il Allen screws either, I could just about get a couple of the strings twanging but no good at all really.
( I quite like a low rattly Entwistle action but this is ridiculous! )
So, after a coffee and a couple of Tunnocks choc wafers, I conclude the next step would be to make 4 shaped flat shims or spacers to sit under the units and raise them up a bit (or a lot)
These I shall make from Metal, I like metal it's a material I'm happy working with, unlike wood which I dislike dealing with (although it does burn well)
I could perhaps bung a few washers under one of the units just to trial how much I need to raise them, and thus how thick my shims need to be.
If it fights me further with this I'll prob do the '' chop out a single square recess" plan b thing, with this I could the use a single sheet of metal, drilled appropriately, instead of 4 strips. I'll see what metal I've got lying around and take a view...
The pic doesn't really show the above issue too well, but even with saddles right up it's really no use unfortunately
edit... I also notice, confirmed by measurement, that the slots are deeper at the front rounded end by quite a bit, therefore making the units tip forward slightly, I'll prob have to level them before doing shims, I'm tempted to just chop the lot out now a'la plan B..