It is a Ford Pinto engine, yes, but in its 2.3 litre OHC version.
It seems this particular version was also known as the Lima engine after the plant in Lima, Ohio, where it was also built.
So only the smaller-engined Pintos used engines made in the UK; the larger engine seems to have been made in the US. You live and learn.
The car had a BW T5 gearbox.
Let's call it solved!