Hi Lee,
Others may appear with different answers, but I've never had much luck with any of the so-called manifold paints. They look ok for a while, but a rusty bucket if painted will look good for a while, too. You can paint the intake manifold part. As for the heat riser valve, I believe you'll have a much better chance of making it work once the manifold is off and you can see things better. Usually if you're patient you can get them to work again. As for the carb linkage pivot, please keep in mind the screw for it usually goes into the water jacket. At least on every 235 I've ever worked on it does. I can't think of much other than that. You'll have a bit more room to adjust your steering box with the manifold out of the way and if you need to replace the drain cock with a new one (at the rear of the engine) that will be easier. Good luck.
