The SAE vs. METRIC can be a LONG List of items.
Basically anything that was NEW to the roadster after
67.5 model became metric:
Engine (U20 and 5 main R16, for example) will have
Transmission (5 speed).
So you soon become a sleuth in figuring out what
was redesigned over time, and what bolts go where!
Seems anything on the "new" safety dash is Metric,
ditto on the 67.5 panel for SOME screws.
I used to say "all body hardware" was SAE fine, but
yet the later doors and striker plates have METRIC
hardware on them. I suspect my 68 2000 was such an
early body shell (still fitted with the original
glass fuel filter); that many of the bolts are SAE.
When I looked at later high windshield cars, they
have metric bolts (10 mm bolt head on door hinges,
vs. a 7/16" bolt head of the 1/4" bolt of earlier
Other things, like the suspension; braking system;
fender bolts; remained SAE fine thread through out
67 and earlier cars should be ALL SAE. No metric
threading appeared until 67.5.
For 67.5 Nissan used a FRENCH standard for the
metric threading. So on the CARBS & Alternators
you will find some odd ball screws that are metric,
but with a strange thread (5 mm x 0.75mm pitch).
Take extreme care as those screws are near impossible
to find (Ahem, I made some on a metal lathe...
threading is CLOSE is 34 tpi; a major nightmare to
For 68 and later: NIssan used a ISO standard on
the threading. Much more common, and 5 mm screws
have 0.80mm threading, easier to replace.
Of course there are some quirks, as The Japanese
preferred 12 mm and 14 mm nut sizes, USA and Germany
went with the 13 mm and 15 mm items.
Sometimes pure luck plays out, as the brake lines
really are 7/16", so I recommend buying a 7/16"
flare nut wrench. Well, by chance, an 11 mm flare
nut wrench happens to fit just fine.