The F7P (1764cc 16v) and F7R (1998cc Williams) engines are very similar. The main differences are in the bottom end - like the crank and so on - so nothing youd really notice in general servicing. The inlet manifolds and heads are of the same design, although the Willy has 32mm inlet valves and the 16v 30mm inlet valves (youd never notice). Bits like the spark plugs, dizzy cap, oil filter and air filter are the same, and any minor variation will be due to the age of the cars (Phase1, 2 etc). The only other main differences that the Willy engine has is the manifold and starter motor.
The confusion may arise becuase the 19 16v uses the same engine as the Clio 16v, but has a different inlet system (including the airbox). Ive been to loads of places that have tried to sell me 19 16v bits.
There are also two other 8v SOHC 1.8 engines available in the Mk1 Clio range (both variants of the F3P).