Please don't misinterpret this, but, if this is your first "performance motor build" then undertaking the direction you're contemplating, may not be highly advisable. To achieve quality results requires knowledge, experience, and lots of specialized tools. There's no "book" for following a Hi-Po 750 build recipe. Some of the information is available, but lots of it is esoteric and buried within the deep recesses of the experienced folks. Meaning; its not documented.
Establish a budget. Locate and arrange a qualified engine builder. Accumulate the parts you know you want and will need, then rely upon them to assemble and assure its proper function. Tuning will best be handled on a dyno, backed by good advice from the myriad of folks on the HiPo forum. Whatever you seek, its probably been done (with mistakes, errors and lessons learned) before so you can avail yourself of their wisdom and avoid the pitfalls.
Clearancing parts to 0.000s is not something most people can do in their garage without ample micrometers and dial gauges, and other tools. You can certainly contract a number of reputable places to build you an engine complete, or subcontract aspects out (head to Mike Rieck, crank to APE, trans work to Fast...) and then have a local shop assemble to spec. Theres no shame in relying on professionals to do professional work. You get the enviable task of putting together a wish list of quality parts and features, they take the brunt of responsibility for accuracy.
If you remain steadfast in your desires, then start with a less ambitious project to cut your teeth and limit your cost/damage would be my parting advice.
Either way, I hope to see a top shelf engine in your project soon!!!