Last season noticed manifolds on port side of both engines began to feel hot (no longer just warm) to the touch; believe these are the originals; removed one (extremely heavy) and am now in the market for a quality replacement; hoping to replace with something that is close to same configuration to avoid reconfiguring exhaust behind it; any insight or if you experience with this project - thanks

Harpurs Marine at one time had a really nice kit for those with deck clearance issues. I installed one of these kits on a 410 and it was absolutely plug and play. It uses Mercruiser style Center riser manifolds with Harpurs adaptor for the risers and fiberglass tubes, hoses and clamps, to bring the discharge down and out as the original style mans did. Contact them for details. http://www.harpursmarine.com/