nice work, not only is that engine well detailed...it appears technically correct down to the heating tube for the automatic choke assembly.
I do have a have a question about the black wire that seems to be attached to the starter. In my experience with full size cars a ground wire was not usually attached at the starter motor, however a small bundler of one or two wires usually were connected to the starter solenoid (smaller cylinder on top of the starter motor on GM products) along with the larger cable coming from the positive side of the battery. The actual starter motor is fed power by a robust strap that is also attached to the solenoid.
not that you need to change anything.