www.massfloefi.com makes a great fuel injection system that is hassle free. It costs around 4 grand and then you will spend another grand on the fuel system. It makes great power as well and i really dont think that it leaves much on the table. I love the look of the stack injection, but some of them are an enormous hassle to tune.
From my research, i would go with a newer shelby, pond, or genesis block. There are just too many questions concerning the older FE blocks and the chance of finding one that hasnt been molested are slim to none.