Stalling problem with new toy

[GMC69]

Well I picked up my new toy yesterday
http://67-72chevytrucks.com/vboard/s...d.php?t=251272

So today I decided to start her up. I had to put it on charge for a few minutes, and then she started right up. My problem is that it will not stay running. I have to keep it revving so it doesn't stall, but then if I keep it a constant rpm, it starts to bog down, so I have to feather the throttle and it keeps it running. As soon as I let go of the gas and it drops in rpms it stalls. My guess is that it is due for a new ( rebuilt) carb as my first step. I used to have a Haynes manual around here for my 69 GMC but I just can't find it, so I will go get one this weekend.

It may be too much fuel cause when I am feathering the throttle and give it a good shot of gas, the exhaust is a bit black. But when revving, it's fine.

I haven't really dug into this truck yet and this was one of the first things on the list to get fixed, since I am NOT pushing this thing around while working on it, lol.