Suggestions needed for a carb and convertor

I think you may want to take a close look at that engine before you run it. EM engines are not designed (normally) to make power in a chassis. They're dyno mules. You may want to ajust the camshaft and valve spring pressures. Maybe static ratio too. I think any convertor will feel sluggish on the street with that combo. I would go with an 8", not 9.5". A modern version is driveable but can be had with a high stall and some efficiency at the higher rpm ranges.