Fuel injection to carburetor camaro.?

Hi I have an opportunity to purchase an 87 camaro 28z. The car originally had a fuel injection engine but the owner had changed it into a carburetor engine. Now Im no car expert but from what I was taught is that the fuel pump is in the gas tank and something needs to be changed. What needs to be done? What is the cheapest way to get the car able drive? About how much will it cost and how long will it take? Also could you explain why. Thank you.
I would actually like to make myself a little more clear. I don't know anything about cars in this department.