Runs terrible after sitting over night - Need HELP

[hooverfish]

My 72 350 4v has a problem. After sitting over night it runs terribly rough, billows smoke (black with some blue color). I can get it out of the drive and down the street. In about 3-5 minutes it straightens out and runs good.Next day it does the same thing running terrible on startup.
I changed plugs and went one range hotter (AC R45TS) gapped at .050 with HEI dist. No help. Plugs show dry black soot with very tip grey color. The exhaust leaves two black patches on the drive where it blows out soot and a few drops of water. I have a restored quadrajet from Bob Stone that's 2 yrs old.

I've been reading threads on valve seals, guides, and valve seats, etc. Not sure if I should replace the seals or get a new pair of heads? But in a way I think it might be a carb problem with the soot and smell of gas in the exhaust smoke.
Hate to spend money without being sure the problem is diagnosed. I'm no mechanic and I don't really have one I trust with this type problem.

Any ideas or suggestions appreciated.