Don't get it right, just get it running. 85 318 roller

Your main investments will be induction and ignition, new or used.
In '85 what you had was Lean Burn with a feedback 2 bbl. carb and one of a couple of different goofy (possibly locked) distributors, so none of that stuff is going to be of any use to you. It's all stuff that's easy to find used, though. Happy hunting!