You could contact Dave or Chris at Modern Muscle or Hotwire, they can sell you a wiring harness that is plug and play with stock ecm.
You will have to change the oil pan, TTI mounts, TTI headers with a manual box or you can change to a Borgeson Power steering box, TTI now making headers to fit that box.
Need a special flex plate to bolt up to a small block auto trans or modern manual or auto.
Will need to fab up an efi fuel system , in tank works the best with a corvette style fuel filter.
3g Style radiator with inlet and outlets on passenger side
Assuming you are running a manual gearbox and 727 auto, expect cost to be around $3500+ for items listed .