You'd think the answer would be simple wouldn't you ?

....
The Vintera 60s JM had a new bridge part number (7705076000) we hadn't seen before (IIRC), which is curiously described as in the parts manual as MUSTANG BRIDGE W/THREADED SADDLES. But it's not a 'Mustang' bridge, since it's got vintage-style, threaded-barrel, height-adjustable saddles.
https://offsetguitars.com/forums/viewto ... 2#p1623502
In any case it's assumed to be an imported metric bridge (as on all MIM offsets). And as such,
both bridge height screws and saddle height screws should all be the same size, as they have always been on MIM guitars' metric offset bridges (vintage-style and Mustang-style) - they are almost certainly all M3 grub screws
that take a 1.5mm allen/hex key.
But to confuse things, the last page of the parts manual says the saddle height screws take a 0.070" hex key (which would be 1.78mm). And as I said, bridge height and saddle height grub screws are always the same size. But since 0.070" has never been a bridge hex key size on any offset bridge before, it's almost certainly wrong (but one can never be 100% sure of such things with Fender). But it may mean if you ring Fender or an authorized dealer they will tell you it's 0.070".
https://www.fmicassets.com/Damroot/Orig ... 1_2019.pdf
Incidentally, if it were an MIA offset bridge, the (Imperial) bridge and saddle height screws would all be #4-40, and the hex key 0.05"/1.27mm (so MIA is not really a possible explanation for the 0.070" figure).
Anyway, let us know if the 1.5mm allen key works ... as it should.