Think it's time to get some new pipe for the 235 3100. The PO had the exhaust manifold made into a double manifold for dual ehaust. It was a common practice back then to achive dual exhaust. I would like to go back to single exhaust and get the weight off the welded piece of exhaust manifold which was added. A cap off plate. In this way I do not have to remove the manifold and install a single. Are there any problems with this thinking? The weld seems solid but the manifold is old and the extra weight of another pipe system will in the future produce a large hole in the manifold just through age and vibration but where and when.