A simple carb swap turned out to be a semi-big project. I didn't know that the Carter AFB was a square bore, so the intake needed to be swapped too. I had an Edelbrock 2101 out back so I cleaned it up and slapped it on. Now the temp sending unit interferes with the coolant neck and needs to be relocated to the head. But that actually helps get better readings, so it's not a bad thing. However, the new sending unit I bought came with a plastic piece for the connection but no connector. And every dang auto parts store said they don't have them. Even went to radio shack and some other specialty stores. COME ON PEOPLE! I know they make these things because here is proof in my hand!! Finally after 3 hours of driving around in 106* heat and no AC I went to a different NAPA, and they had what I needed so I bought 2. Now I need to lengthen the wire and rout it to sending unit so it won't hit the ram horns.
To me the engine just looks better with a quadrajet sitting atop the intake. Just looks right. After firing it up last night, minus the sending unit being relocated, it fired right up, fast idle was a tad high, and I finally got the fast idle to kick down to idle. Then I saw gas pooling on the intake. CRAP!! Added more pvc paste to the fittings and tightened them a little more, and that fixed the leak. But then the engine wouldn't settle down when I started it again. I suspect the intakes gaskets didn't seat properly. I will check that out tonight after I relocate the sending unit. In any case there is a massive vacuum leak. Another oddity, the factory air cleaner housing I bought that is supposed to fit a 68 truck, the bottom of the air cleaner housing hits the throttle arm of the carburetor. So I may need to find a different housing. If I do I need to find one with the air intake on the driver's side so I can run the air intake hose to that side instead of under the battery tray. There isn't any room under there. I need to get creative for the air intake hose and how it draws air in from the front of the engine bay. I may go with something like I see on my Subaru, a long thin opening that the hose attaches to. I just know I want the air coming from outside the engine bay.
Here are some pics of the new carb and intake on the motor.