Choke is staying on too long?

[Momboy007]

Hello All,
I have what I hope to be a quick question.
My choke on my completely stock 396 works just fine, it simple stays on too long. It is an original 4M Carb (if that helps at all)
The fast idle appears good and when it is fully warmed up, it runs very well, it just seems when first fired up in the morning the choke stays on way too long and the truck runs terrible, or until fully warmed up, lots of smoke (black) in the mean time and running way, way too rich. I tried reading the manual on how to adjust the choke, but in all honesty, I did not "GET IT".
It is a California truck and, like I said completely stock, even has the smog pump connected.
P.S. the truck now has 36K miles on it now.
Thanks in advance for any help
Rick