or go totally off teh beaten path, and make your own way
ie: practical performance car's editor is dropping 27litres of V12 tank engine into a rover SD1, now that is class. and whilst i accept it would be yight to shoehorn into a big rover, and nigh on impossible into a punto, i'm sure a little fettling, measuring, persuaion and you could go totally left field. alfa v6 anyone?!