You'd have to select a carb that is matched to the engine size, overall flowrate, and is known to work with a turbo. Either one carb or dual/quad sidedrafts
Then have a custom intake manifold made to fit between the head and the carb. Have to add fittings to the manifold for the heater core, or find a way to re-route them
Rip out the stock pump and EFI system. The ignition system still needs the ECU to be there, so you can't exactly delete all that unless you find a standalone distributor. Which I'm guessing the point of running a carb is to delete the ECU? idk. This has been asked several times now, the EFI system is really super simple in the Capri
Have to find a way to pressurize the bowl in the carb(s) so it will work with boost, and have it jetted/tuned (best done on a dyno, WBO2 is still a must even for carbs) Even still, it's only good for lower boost levels. At higher boost the carbs don't really "see" the denser, higher pressure air so it gets very hard to tune right
All to do what, might I ask? Aside from being "unique" you're not going to match the performance/refinement of the stock EFI system, let alone a better system like Megasquirt
If you google around, something like
"turbocharger + carburetor" you'll find a lot more in-depth info of what it would require to set up