Denny,
The Clifford heat plate that fits under the carb is not going to help heat the manifold, which is where you need it - It "may" provide some improvement in extreme cold weather operation but doesn't address the problem of keeping the mixture in suspension when it enters a cold manifold. And unfortunately, the older Clifford intakes didn't include the connection for the stock heat box - they were designed for use with tube headers. I think you'd be better off replacing the Clifford intake with a the later version, or look for an Offy with the heat box connection.
As for gaskets, I've always liked the Clifford one-piece intake/exhaust gasket because they are easier (for me, at least) to install. Only one piece to align and keep in place instead of 3. And they seem to hold up well, too. I'm sure these are sourced from another maker, but as Gearhead mentions, Langdon's Stovebolt is a stocking Clifford dealer and should be able to help you.
