I believe you are going to run into things like you are seeing while getting your beauty back to operating condition. Don't worry you can get there. Everyone here is rooting for you and will help when possible. Your issues with the fuel and now the cooling systems are normal for an engine / car settings for an extended period of time. I normally look at each part of the systems and clean, fix or replace everything that needs replacing. I seen your first post and you have a great 65 to start. For the fuel system I'd follow the advice as you are starting. I would make sure the lines are clear and replace any rubber lines. A new fuel pump wouldn't be a investment. As the advice says clean or replace tank and sending unit, fill the fuel bowl in the carb and it should run until it primes the pump, repeat primming if needed. As for the cooling system have the radiator cleaned, replace the water pump and thermostat, flush the engine and fI'll with coolant and water. Then you will be off to all the other things you will encounter but you are not over your head, just enjoy the though of riding in a beautiful classic Mopar after your finished.