2002 Firebird. GM 3800 series 2 V6 engine. Clouds of white smoke and shuddering.

What is your question?

I am relatively new to this. I bought this car last october. When I got it, and since I have had it, it has had white smoke coming out of the exhaust. I drove it like that for 8 months. I finally got another car, so I decided to try and do the head gaskets. The car was running fine before I started the job, other that a little white smoke when idling. I parked it in our side yard, since the garage is full. At the time, I didnt realize I would need to get under the car to do this job. I started taking apart the engine, making my way down to the head gaskets. I took out the radiator so that I could sit in the engine bay while I worked. I got the entire intake manifold off, top and bottom, and everything attached to it. I started taking off the valve covers. I got one off, but the other one had a stripped bolt, so I couldn't get it off. I decided to come back to it and went ahead and disconnected the headers from the heads. Then I realized I would have to get completely under the car to completely remove the headers from the car. With those two big problems, I realized I wouldnt be able to finish the job where the car sat. So I started putting everything back together. I replaced the lower intake manifold gasket and the plenum gasket, as well as the little one on the throttle body. I got everything back together, and I filled the radiator with distilled water because I dont have any money for coolant right now. I went to start it, and it didnt crank the first time, which I expected. I let the fuel pump run for a few seconds, then I tried again. It slowly, barely shuddered to life and big clouds of white smoke started coming from the engine bay and the exhaust. I shut it off after like 5 seconds of the smoke and shuddering. I have no idea why this happened. It didnt happen before I parked it. Did I put it back together wrong? Or what?