According to Ken Hill's book:

There were 122 Fiat engined Plus 4s. 90 were 2 seaters and 32 were 4 seaters.

Additionally there were 93 Fiat engined 4/4s. 47 were 2 seaters, 35 4 seaters, 1 works 2 seater, and 10 were 2 litre cars.

1972 4/4 2 Seater