can trace its roots all the way back to may 1982 believe it or not ! the other give away is that the 1.6 and our 1.7 (which were evolved from it) are the same stroke as all the 1.6 and 1.8 big block engines (79.5)
cant really miss the gearbox F number as its cast (raised lettering) into the top of the box, just below the output shaft on the slector turret. they are big too like 1.5 inches (the typeset i mean, not that its raised 1.5 inches) i have seen a couple of examples with out an F number though
generally speaking F10, F13, F15, F17 are small block
F16, F18, F20 are big block.
there are crossovers (which i think is due to the engines being low output) with the obvious examples being our big block engines with small block gearboxes, which use special flywheel clutch combination to make that possible
in that list i cant see any small block engines with a big block box!