[old Chevy guy]

That yellow wire from the starter goes to the coil on a points ignition to prevent voltage drop to the coil while cranking the engine,not needed with hei .The big orange,used to be purple,wire on the small post closest to the block comes from the ignition switch to trip the solinoid and make the starter go. you did'nt say whether she turns over or not,Im guessing not if you changed the battery. If that purple wire is disconected somewhere the starter wont turn over.Is it an automatic? If so check the neutral safety switch,its inline in that purple wire under the dash.If you can see it you can try jumping the Purple terminal to the battery cable post on the starter with a screwdriver,making sure your all in neutral of course. I sarted my camaro like that all the time when there was a bad conection somewhere.