I went ahead and mounted the NOS, nutted NGC 450's last night, regardless of the recessed mounts on the frame. The nuts seemed to do an adequate job of centering the brakes, so I'll leave them as-is for now unless it proves problematic in the future.
The crankset is a mockup, for the Nuovo spindle I have installed is pitted. Anyone have one for trade? Thick cup spindles only.
The NGC 450's have far more of a "traditional Paramount" feel then the Royal Gran-Compes, if you ask me. Fits the bill for the "traditional-build Paramount w/80's components" look.
Take care,
-Kurt