Thanks Ed
My 460 has a bunch of vacuum line around the carb and distributor that all seem connected, but there is a big hose with a bolt in it coming off the back of the intake manifold. I'll see what lies there first, and then check out the carb. Your picture of a truck looks quite similar to mine but cleaner! Have you ever converter brakes over to a power booster and if so, what modifications to the brake lines did you need to make?