I have never built a motor, just looked and done dream builds lol. So take anything I say with a grain of salt...
Maybe its because I am lazy but I have always thought that if I was going to build a motor I would pick up a built short block from a company, or even a built longblock. Just because they have most likely gone thru the research and development to properly assemble the motor and make sure that components work well together.
If you would like to explore this option
Axis is popular
http://www.raw1performance.com/index_files/Page678.html
GST also has built blocks that they have put together, but also have Cosworth blocks
http://www.gstmotorsports.com/store/...=71_82_159_342
Thats just my $.02. Oh, and if I were you I would get in touch with a tuner and have them guide you thru your build so they are in the know when it comes time to tune your car.