I'm a big fan & user of the Q-jet carb but pulling the kind of loads you are talking about with that small engine, I think a square bore would be better. With the tiny primary side bores of the Q-jet you will be back & forth out of the secondaries. That is why the big trucks used big 2 barrel carbs or squarbore Holleys. I would also use an aluminum manifold as long as I was changing. I think an Edelbrock carb would be best.
