I agree there are some truly hideous deisels around, many of which have been Fords! I'd only do it if I could aquire the very latest turbo deisel (impossible for me!) from say Audi/VW which I have the good fortune to drive regularly.
This engine is not noisy, and the turbo is actually MORE economical than VW/Audi's previous non-turbo deisel. It averages 55mpg in very mixed driving. Consistent cruising sees 70mpg - no that's not a typo. It produces 110bhp (more than a pinto) a shedload of torque (miles more than a pinto) and while it may be finished at 5000, by that time your Capri is a speck in my mirror! And besides, I pity you if you take your Capri to 5000rpm when it will be sounding as hideous as a Fiesta 1.8D while the carb throws bucket loads of our precious LRP into the engine!
I am however, about to (almost) complete tuning my pinto cylinder head for economy with high torque cam, weber 38 carb which is also big on torque, and a strategically gas flowed cylinder head. Will keep the board posted on the results!
Andy P