That tyre measurement is roughly the same as mine within a couple of mm or soMay be your issue is tyre type used and the tyre profile is just to deep.
My tyre profile is 38mm deep from the rim edge and 376mm from axle C/L to tyre outer edge.
but it`s this measurement of yours that`s important i think "My mesurements are C/L of BB ot C/L of axle in drop out 430mm. "
this new frame is only 425mm, that extra 5mm would make all the difference..
long story short, it has to go back, was trying to avoid that with building it all up and getting that headset installed etc etc, bit of a pain,
Anyhow many thanks for taking the time to measure up there..