I'll look for some pics when I get home. I bought a kit from quadrajetparts.com for the electric conversion. Theres no need to block off the vaccum into the choke valve body as it is a metered leak. You can just cap the outlet where the solid pipe would normally go into the body. On mine there is a solid pipe that loops from the choke body down into the port on the intake manifold. Then another one that looped up and connected to the nipple on the top/back of the carb. On yours, you can see that nipple has a cap on it. The rear pull-off had a hose going down to a nipple at the rear/base of the carb.
It gets VERY hot and I had problems with it melting wiring harness to the alternator that got too close. The new motor I'm putting together will be using an older intake manifold that didn't have an EGR or hot air choke port on the manifold. If you want to keep the same manifold, I'd recommend just creating your own blockoff plate and use a stock gasket to seal it off. The electric conversion kit was less than $50... I don't remember exactly how much though. If the truck is an unknown age, I'd recommend you order a rebuild kit and the conversion kit together and take the carb off to do it all at the same time. Clean it out real good and rebuild the whole carb and convert it to electric at the same time.
