The 3 litre Essex engined Capri ceased production years before the introduction of the 5 speed box. However, with a little modification, the 2.8 injection's 5 speed "Type 9" will fit.
The most obvious problem being that the "Type 9" was never designed for the Essex engine, therefore there is no obvious bell housing to mate the two. But as the "Type 9" was based on the "Type E" box, we find a whole family of bell housings that date back to the early 70's.
The old MK1 Granada / Consul used the Essex engines in 2.0 litre V4, 2.5 V6 and 3 litre capacities. With the 2.0 and 2.5 litre engines fitted, they were mated to the "Type E" box Thus we find a bell housing that mates to both the 3.0 litre block and the "Type E" box. As in the Capri of the period, the large "Type 5" was fitted with the 3.0 litre which means that the bell housing will not fit "Type 9".
Identifying the Granada bell housing is relatively straightforward as it will bear the part number 72GB 7505 LA cast on the side. It was only used between 1972 and 1974 so they may well be scarce by now.
Upon fitting, the next problem found is that the first motion shaft is 14.7mm too long. It should be ground back this distance to avoid binding the spigot bearing.