I would use the stock '74 balancer. All the brackets, pulleys and belts will fit as before and be stock for that year.
There should be two different size manifold hold down clamps on your '74 engine. The long type, pictured below, is too long. You will need a total of six short ones and they may need modified slightly. The head originally had two of the studs (pictured below) and two end stud pins that you have already replaced.
Your manifold hardware now includes course thread nuts, fine thread nuts and course bolts. I put stock studs from one end of the head to the other and can use the same size nut at every location.
Nice valve cover, but are you planning on using a PCV?
You are also in need of a vacuum source for the power brake booster which I assume is standard on '74. The clifford has a spot on the back for that, but needs drilled and tapped.
292 and 250 pump are the same.
