Hi there. Welcome to our site!
Well, that's why they call these things "projects", don't they? ;-)
What kind of bronco are we working on, full size or II? What size engine? Auto or stick? 2 or 4WD?
Does the new starter cranks the engine around when you turn the key to START? If it does, but the engine still won't start, then we need to find what is causing the engine not to start; is it lack of compression, spark, fuel pressure or injector pulse? Once we find which of those is missing, we can then focus on diagnosing the corresponding system and pinpointing the problem. Sounds good?
We should start by trying to start the engine with starting fluid; if it starts and runs momentarily, then we'll know compression and spark are good. If that's the case, then we'll need to test fuel pressure and injector pulse - we're looking for 35-45 psi fuel pressure and a steady flash from a Noid light for injector pulse.
Please run those tests and get back to me with the results so we can continue.