The disc brakes are of the 4-pot variety, originally from a Y-reg MG Metro. There was much debate as to the route to take - i.e. go to 12" wheels and use the Metro brake setup as-is, or modify the brake setup for use with 10" wheels.

I chose to go for the 10" wheels, as my car has the standard 10" steel wheels. However...
As you can see, there's not a whole lot of room to fit it in.

In fact, closer examination shows that it's never going to fit :(

The next phase of the conversion is to modify the caliper to match the reduced caliper diameter.

Then the search will be on for some wheels to match...