If you cant rid of it stu,mightbe intersted in a couple of bits,i owe you a bottle of scotch m8 for that amp,it seems to have done the job. What condition that stering wheel m8 ?
I would get some quotes for the work first. Having an engine rebored ,crank ground and new bits is expensive. Might be worth getting quote for an exchange engine. Other option is if you want more power picking up a low milage mondeo or focus 1.8 or 2.0 litre zetec engine. Or fitting an 1.6 mfi rs turbo set up.