Need /6 help

Hey all. Well after some thinking, reading and bill fighting, I am wanting to rebuild my / and KEEP IT IN MY DART. :cheers: Yes, I said keep it. I was thinking of a 360swap but since have changed my mind. I do have a few issues with it right now.
I went to change the valve cover gasket, went to the parts store told them it was a 71 Dart with the 225. Got my gasket, went home and it was the wrong one. So I took the cover with me to exchange the gasket. There was an "older MoPar guy" there and he said that it looked like a newer cover. So we looked up a 83 Ram truck with a 225 and it was the gasket I needed. So my first question is, how can I tell what year the moter is?

Right now it is not running well. It will start right up but has gray smoke and smells like fuel. I rebuild the 1920 carb thinking that was the issue. Still smokes and smells. I have had people tell me to pull and read the plugs. Although I have fiddled with cars for a long time never learned to read the plugs. What would I be looking for?
I am looking at getting another / so I can rebuild one and still be able to drive the car till its done. So soon I will be looking for a parts list for the build. I want it to be streetable, will not see the track just street. I want it just quick enough to have fun with but still get "good" gas mileage. Mostly drive at cruises.

So what advise you folks are willing to share with me?