Five year old crate engine

The work has slowed for lack of money, but the car is still waiting for me. I got the flexplate bolt tightened, a nice adventure.
Now I have to figure out the fuel and exhaust. I'm keeping the stock exhaust for now but can't put it on because of it being 40 years old and rusty. The gas tank is going to need drained and cleaned- no rusty tank goo in the nice new block. And I still haven't done anything to the manifolds. I have two pair that are different.
If I go with the old choke I need to find a choke cup thingy, or figure out how to do an electric. I also have 2 1920 carbs that have different numbers on them and want to do the original carb. And, how do you change manifold studs, I have a new set but the nuts have a different thread pitch?