Steve,
it is my understanding the mkIIs, did not use the mkI nose at all, but a modified version of it to start with.
You will notice there is no central air scoop on the mkII front clips up by the screen for the screen demist/heater.
This was due to the repositioning of the spare wheel to accomodate the front mounted oil tank for the dry sump, which caused the redesign of the vent panel too, which had a slightly different shape and had external hinges. The type & location of wiper motor had to be repositioned too.
The raised wheel arch version of front mkII clip was adopted following the 1966 Daytona meeting, when the front tyres started to rub holes in the front clip, so they put raised patches on, and subsequently modified the actual clips.
Note that the central vent panel changed between races, let alone between cars !
Without a doubt your best source would be to go buy/borrow the book 'The ford that beat Ferrari' by John S Allen. It also has a picture of 1031 in the pits at Lemans in its dark blue colours, Page 116
There are other good books out there, but this one will give you loads of info.
I hope that helps.
Cheers,
John.